R/english.R

In friendlynumber: Translate Numbers into Number Words

# comments ---------------------------------------------------------------------

# Here's a potentially faster and more precise way to do this (that I might try)
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  " duoquinquagintillion", " tresquinquagintillion", " quattuorquinquagintillion",
  " quinquinquagintillion", " sesquinquagintillion", " septenquinquagintillion",
  " octoquinquagintillion", " novenquinquagintillion", " sexagintillion",
  " unsexagintillion", " duosexagintillion", " tresexagintillion",
  " quattuorsexagintillion", " quinsexagintillion", " sesexagintillion",
  " septensexagintillion", " octosexagintillion", " novensexagintillion",
  " septuagintillion", " unseptuagintillion", " duoseptuagintillion",
  " treseptuagintillion", " quattuorseptuagintillion", " quinseptuagintillion",
  " seseptuagintillion", " septenseptuagintillion", " octoseptuagintillion",
  " novenseptuagintillion", " octogintillion", " unoctogintillion",
  " duooctogintillion", " tresoctogintillion", " quattuoroctogintillion",
  " quinoctogintillion", " sexoctogintillion", " septemoctogintillion",
  " octooctogintillion", " novemoctogintillion", " nonagintillion",
  " unnonagintillion", " duononagintillion", " trenonagintillion",
  " quattuornonagintillion", " quinnonagintillion", " senonagintillion",
  " septenonagintillion", " octononagintillion", " novenonagintillion",
  " centillion", " uncentillion", " duocentillion", " trescentillion",
  " quattuorcentillion", " quincentillion", " sexcentillion", " septencentillion",
  " octocentillion", " novencentillion", " decicentillion", " undecicentillion",
  " duodecicentillion", " tredecicentillion", " quattuordecicentillion",
  " quindecicentillion", " sedecicentillion", " septendecicentillion",
  " octodecicentillion", " novendecicentillion", " viginticentillion",
  " unviginticentillion", " duoviginticentillion", " tresviginticentillion",
  " quattuorviginticentillion", " quinviginticentillion", " sesviginticentillion",
  " septemviginticentillion", " octoviginticentillion", " novemviginticentillion",
  " trigintacentillion", " untrigintacentillion", " duotrigintacentillion",
  " trestrigintacentillion", " quattuortrigintacentillion", " quintrigintacentillion",
  " sestrigintacentillion", " septentrigintacentillion", " octotrigintacentillion",
  " noventrigintacentillion", " quadragintacentillion", " unquadragintacentillion",
  " duoquadragintacentillion", " tresquadragintacentillion", " quattuorquadragintacentillion",
  " quinquadragintacentillion", " sesquadragintacentillion", " septenquadragintacentillion",
  " octoquadragintacentillion", " novenquadragintacentillion",
  " quinquagintacentillion", " unquinquagintacentillion", " duoquinquagintacentillion",
  " tresquinquagintacentillion", " quattuorquinquagintacentillion",
  " quinquinquagintacentillion", " sesquinquagintacentillion",
  " septenquinquagintacentillion", " octoquinquagintacentillion",
  " novenquinquagintacentillion", " sexagintacentillion", " unsexagintacentillion",
  " duosexagintacentillion", " tresexagintacentillion", " quattuorsexagintacentillion",
  " quinsexagintacentillion", " sesexagintacentillion", " septensexagintacentillion",
  " octosexagintacentillion", " novensexagintacentillion", " septuagintacentillion",
  " unseptuagintacentillion", " duoseptuagintacentillion", " treseptuagintacentillion",
  " quattuorseptuagintacentillion", " quinseptuagintacentillion",
  " seseptuagintacentillion", " septenseptuagintacentillion", " octoseptuagintacentillion",
  " novenseptuagintacentillion", " octogintacentillion", " unoctogintacentillion",
  " duooctogintacentillion", " tresoctogintacentillion", " quattuoroctogintacentillion",
  " quinoctogintacentillion", " sexoctogintacentillion", " septemoctogintacentillion",
  " octooctogintacentillion", " novemoctogintacentillion", " nonagintacentillion",
  " unnonagintacentillion", " duononagintacentillion", " trenonagintacentillion",
  " quattuornonagintacentillion", " quinnonagintacentillion", " senonagintacentillion",
  " septenonagintacentillion", " octononagintacentillion", " novenonagintacentillion"
)

english$illions <- c(
  "thousand", "million", "billion", "trillion", "quadrillion",
  "quintillion", "sextillion", "septillion", "octillion", "nonillion",
  "decillion", "undecillion", "duodecillion", "tredecillion", "quattuordecillion",
  "quindecillion", "sedecillion", "septendecillion", "octodecillion",
  "novendecillion", "vigintillion", "unvigintillion", "duovigintillion",
  "tresvigintillion", "quattuorvigintillion", "quinvigintillion",
  "sesvigintillion", "septemvigintillion", "octovigintillion",
  "novemvigintillion", "trigintillion", "untrigintillion", "duotrigintillion",
  "trestrigintillion", "quattuortrigintillion", "quintrigintillion",
  "sestrigintillion", "septentrigintillion", "octotrigintillion",
  "noventrigintillion", "quadragintillion", "unquadragintillion",
  "duoquadragintillion", "tresquadragintillion", "quattuorquadragintillion",
  "quinquadragintillion", "sesquadragintillion", "septenquadragintillion",
  "octoquadragintillion", "novenquadragintillion", "quinquagintillion",
  "unquinquagintillion", "duoquinquagintillion", "tresquinquagintillion",
  "quattuorquinquagintillion", "quinquinquagintillion", "sesquinquagintillion",
  "septenquinquagintillion", "octoquinquagintillion", "novenquinquagintillion",
  "sexagintillion", "unsexagintillion", "duosexagintillion", "tresexagintillion",
  "quattuorsexagintillion", "quinsexagintillion", "sesexagintillion",
  "septensexagintillion", "octosexagintillion", "novensexagintillion",
  "septuagintillion", "unseptuagintillion", "duoseptuagintillion",
  "treseptuagintillion", "quattuorseptuagintillion", "quinseptuagintillion",
  "seseptuagintillion", "septenseptuagintillion", "octoseptuagintillion",
  "novenseptuagintillion", "octogintillion", "unoctogintillion",
  "duooctogintillion", "tresoctogintillion", "quattuoroctogintillion",
  "quinoctogintillion", "sexoctogintillion", "septemoctogintillion",
  "octooctogintillion", "novemoctogintillion", "nonagintillion",
  "unnonagintillion", "duononagintillion", "trenonagintillion",
  "quattuornonagintillion", "quinnonagintillion", "senonagintillion",
  "septenonagintillion", "octononagintillion", "novenonagintillion",
  "centillion", "uncentillion", "duocentillion", "trescentillion",
  "quattuorcentillion", "quincentillion", "sexcentillion", "septencentillion",
  "octocentillion", "novencentillion", "decicentillion", "undecicentillion",
  "duodecicentillion", "tredecicentillion", "quattuordecicentillion",
  "quindecicentillion", "sedecicentillion", "septendecicentillion",
  "octodecicentillion", "novendecicentillion", "viginticentillion",
  "unviginticentillion", "duoviginticentillion", "tresviginticentillion",
  "quattuorviginticentillion", "quinviginticentillion", "sesviginticentillion",
  "septemviginticentillion", "octoviginticentillion", "novemviginticentillion",
  "trigintacentillion", "untrigintacentillion", "duotrigintacentillion",
  "trestrigintacentillion", "quattuortrigintacentillion", "quintrigintacentillion",
  "sestrigintacentillion", "septentrigintacentillion", "octotrigintacentillion",
  "noventrigintacentillion", "quadragintacentillion", "unquadragintacentillion",
  "duoquadragintacentillion", "tresquadragintacentillion", "quattuorquadragintacentillion",
  "quinquadragintacentillion", "sesquadragintacentillion", "septenquadragintacentillion",
  "octoquadragintacentillion", "novenquadragintacentillion", "quinquagintacentillion",
  "unquinquagintacentillion", "duoquinquagintacentillion", "tresquinquagintacentillion",
  "quattuorquinquagintacentillion", "quinquinquagintacentillion",
  "sesquinquagintacentillion", "septenquinquagintacentillion",
  "octoquinquagintacentillion", "novenquinquagintacentillion",
  "sexagintacentillion", "unsexagintacentillion", "duosexagintacentillion",
  "tresexagintacentillion", "quattuorsexagintacentillion", "quinsexagintacentillion",
  "sesexagintacentillion", "septensexagintacentillion", "octosexagintacentillion",
  "novensexagintacentillion", "septuagintacentillion", "unseptuagintacentillion",
  "duoseptuagintacentillion", "treseptuagintacentillion", "quattuorseptuagintacentillion",
  "quinseptuagintacentillion", "seseptuagintacentillion", "septenseptuagintacentillion",
  "octoseptuagintacentillion", "novenseptuagintacentillion", "octogintacentillion",
  "unoctogintacentillion", "duooctogintacentillion", "tresoctogintacentillion",
  "quattuoroctogintacentillion", "quinoctogintacentillion", "sexoctogintacentillion",
  "septemoctogintacentillion", "octooctogintacentillion", "novemoctogintacentillion",
  "nonagintacentillion", "unnonagintacentillion", "duononagintacentillion",
  "trenonagintacentillion", "quattuornonagintacentillion", "quinnonagintacentillion",
  "senonagintacentillion", "septenonagintacentillion", "octononagintacentillion",
  "novenonagintacentillion", "ducentillion", "unducentillion",
  "duoducentillion", "treducentillion", "quattuorducentillion",
  "quinducentillion", "seducentillion", "septenducentillion", "octoducentillion",
  "novenducentillion", "deciducentillion", "undeciducentillion",
  "duodeciducentillion", "tredeciducentillion", "quattuordeciducentillion",
  "quindeciducentillion", "sedeciducentillion", "septendeciducentillion",
  "octodeciducentillion", "novendeciducentillion", "vigintiducentillion",
  "unvigintiducentillion", "duovigintiducentillion", "tresvigintiducentillion",
  "quattuorvigintiducentillion", "quinvigintiducentillion", "sesvigintiducentillion",
  "septemvigintiducentillion", "octovigintiducentillion", "novemvigintiducentillion",
  "trigintaducentillion", "untrigintaducentillion", "duotrigintaducentillion",
  "trestrigintaducentillion", "quattuortrigintaducentillion", "quintrigintaducentillion",
  "sestrigintaducentillion", "septentrigintaducentillion", "octotrigintaducentillion",
  "noventrigintaducentillion", "quadragintaducentillion", "unquadragintaducentillion",
  "duoquadragintaducentillion", "tresquadragintaducentillion",
  "quattuorquadragintaducentillion", "quinquadragintaducentillion",
  "sesquadragintaducentillion", "septenquadragintaducentillion",
  "octoquadragintaducentillion", "novenquadragintaducentillion",
  "quinquagintaducentillion", "unquinquagintaducentillion", "duoquinquagintaducentillion",
  "tresquinquagintaducentillion", "quattuorquinquagintaducentillion",
  "quinquinquagintaducentillion", "sesquinquagintaducentillion",
  "septenquinquagintaducentillion", "octoquinquagintaducentillion",
  "novenquinquagintaducentillion", "sexagintaducentillion", "unsexagintaducentillion",
  "duosexagintaducentillion", "tresexagintaducentillion", "quattuorsexagintaducentillion",
  "quinsexagintaducentillion", "sesexagintaducentillion", "septensexagintaducentillion",
  "octosexagintaducentillion", "novensexagintaducentillion", "septuagintaducentillion",
  "unseptuagintaducentillion", "duoseptuagintaducentillion", "treseptuagintaducentillion",
  "quattuorseptuagintaducentillion", "quinseptuagintaducentillion",
  "seseptuagintaducentillion", "septenseptuagintaducentillion",
  "octoseptuagintaducentillion", "novenseptuagintaducentillion",
  "octogintaducentillion", "unoctogintaducentillion", "duooctogintaducentillion",
  "tresoctogintaducentillion", "quattuoroctogintaducentillion",
  "quinoctogintaducentillion", "sexoctogintaducentillion", "septemoctogintaducentillion",
  "octooctogintaducentillion", "novemoctogintaducentillion", "nonagintaducentillion",
  "unnonagintaducentillion", "duononagintaducentillion", "trenonagintaducentillion",
  "quattuornonagintaducentillion", "quinnonagintaducentillion",
  "senonagintaducentillion", "septenonagintaducentillion", "octononagintaducentillion",
  "novenonagintaducentillion", "trecentillion", "untrecentillion",
  "duotrecentillion", "trestrecentillion", "quattuortrecentillion",
  "quintrecentillion", "sestrecentillion", "septentrecentillion",
  "octotrecentillion", "noventrecentillion", "decitrecentillion",
  "undecitrecentillion", "duodecitrecentillion", "tredecitrecentillion",
  "quattuordecitrecentillion", "quindecitrecentillion", "sedecitrecentillion",
  "septendecitrecentillion", "octodecitrecentillion", "novendecitrecentillion",
  "vigintitrecentillion", "unvigintitrecentillion", "duovigintitrecentillion",
  "tresvigintitrecentillion", "quattuorvigintitrecentillion", "quinvigintitrecentillion",
  "sesvigintitrecentillion", "septemvigintitrecentillion", "octovigintitrecentillion",
  "novemvigintitrecentillion", "trigintatrecentillion", "untrigintatrecentillion",
  "duotrigintatrecentillion", "trestrigintatrecentillion", "quattuortrigintatrecentillion",
  "quintrigintatrecentillion", "sestrigintatrecentillion", "septentrigintatrecentillion",
  "octotrigintatrecentillion", "noventrigintatrecentillion", "quadragintatrecentillion",
  "unquadragintatrecentillion", "duoquadragintatrecentillion",
  "tresquadragintatrecentillion", "quattuorquadragintatrecentillion",
  "quinquadragintatrecentillion", "sesquadragintatrecentillion",
  "septenquadragintatrecentillion", "octoquadragintatrecentillion",
  "novenquadragintatrecentillion", "quinquagintatrecentillion",
  "unquinquagintatrecentillion", "duoquinquagintatrecentillion",
  "tresquinquagintatrecentillion", "quattuorquinquagintatrecentillion",
  "quinquinquagintatrecentillion", "sesquinquagintatrecentillion",
  "septenquinquagintatrecentillion", "octoquinquagintatrecentillion",
  "novenquinquagintatrecentillion", "sexagintatrecentillion", "unsexagintatrecentillion",
  "duosexagintatrecentillion", "tresexagintatrecentillion", "quattuorsexagintatrecentillion",
  "quinsexagintatrecentillion", "sesexagintatrecentillion", "septensexagintatrecentillion",
  "octosexagintatrecentillion", "novensexagintatrecentillion",
  "septuagintatrecentillion", "unseptuagintatrecentillion", "duoseptuagintatrecentillion",
  "treseptuagintatrecentillion", "quattuorseptuagintatrecentillion",
  "quinseptuagintatrecentillion", "seseptuagintatrecentillion",
  "septenseptuagintatrecentillion", "octoseptuagintatrecentillion",
  "novenseptuagintatrecentillion", "octogintatrecentillion", "unoctogintatrecentillion",
  "duooctogintatrecentillion", "tresoctogintatrecentillion", "quattuoroctogintatrecentillion",
  "quinoctogintatrecentillion", "sexoctogintatrecentillion", "septemoctogintatrecentillion",
  "octooctogintatrecentillion", "novemoctogintatrecentillion",
  "nonagintatrecentillion", "unnonagintatrecentillion", "duononagintatrecentillion",
  "trenonagintatrecentillion", "quattuornonagintatrecentillion",
  "quinnonagintatrecentillion", "senonagintatrecentillion", "septenonagintatrecentillion",
  "octononagintatrecentillion", "novenonagintatrecentillion", "quadringentillion",
  "unquadringentillion", "duoquadringentillion", "tresquadringentillion",
  "quattuorquadringentillion", "quinquadringentillion", "sesquadringentillion",
  "septenquadringentillion", "octoquadringentillion", "novenquadringentillion",
  "deciquadringentillion", "undeciquadringentillion", "duodeciquadringentillion",
  "tredeciquadringentillion", "quattuordeciquadringentillion",
  "quindeciquadringentillion", "sedeciquadringentillion", "septendeciquadringentillion",
  "octodeciquadringentillion", "novendeciquadringentillion", "vigintiquadringentillion",
  "unvigintiquadringentillion", "duovigintiquadringentillion",
  "tresvigintiquadringentillion", "quattuorvigintiquadringentillion",
  "quinvigintiquadringentillion", "sesvigintiquadringentillion",
  "septemvigintiquadringentillion", "octovigintiquadringentillion",
  "novemvigintiquadringentillion", "trigintaquadringentillion",
  "untrigintaquadringentillion", "duotrigintaquadringentillion",
  "trestrigintaquadringentillion", "quattuortrigintaquadringentillion",
  "quintrigintaquadringentillion", "sestrigintaquadringentillion",
  "septentrigintaquadringentillion", "octotrigintaquadringentillion",
  "noventrigintaquadringentillion", "quadragintaquadringentillion",
  "unquadragintaquadringentillion", "duoquadragintaquadringentillion",
  "tresquadragintaquadringentillion", "quattuorquadragintaquadringentillion",
  "quinquadragintaquadringentillion", "sesquadragintaquadringentillion",
  "septenquadragintaquadringentillion", "octoquadragintaquadringentillion",
  "novenquadragintaquadringentillion", "quinquagintaquadringentillion",
  "unquinquagintaquadringentillion", "duoquinquagintaquadringentillion",
  "tresquinquagintaquadringentillion", "quattuorquinquagintaquadringentillion",
  "quinquinquagintaquadringentillion", "sesquinquagintaquadringentillion",
  "septenquinquagintaquadringentillion", "octoquinquagintaquadringentillion",
  "novenquinquagintaquadringentillion", "sexagintaquadringentillion",
  "unsexagintaquadringentillion", "duosexagintaquadringentillion",
  "tresexagintaquadringentillion", "quattuorsexagintaquadringentillion",
  "quinsexagintaquadringentillion", "sesexagintaquadringentillion",
  "septensexagintaquadringentillion", "octosexagintaquadringentillion",
  "novensexagintaquadringentillion", "septuagintaquadringentillion",
  "unseptuagintaquadringentillion", "duoseptuagintaquadringentillion",
  "treseptuagintaquadringentillion", "quattuorseptuagintaquadringentillion",
  "quinseptuagintaquadringentillion", "seseptuagintaquadringentillion",
  "septenseptuagintaquadringentillion", "octoseptuagintaquadringentillion",
  "novenseptuagintaquadringentillion", "octogintaquadringentillion",
  "unoctogintaquadringentillion", "duooctogintaquadringentillion",
  "tresoctogintaquadringentillion", "quattuoroctogintaquadringentillion",
  "quinoctogintaquadringentillion", "sexoctogintaquadringentillion",
  "septemoctogintaquadringentillion", "octooctogintaquadringentillion",
  "novemoctogintaquadringentillion", "nonagintaquadringentillion",
  "unnonagintaquadringentillion", "duononagintaquadringentillion",
  "trenonagintaquadringentillion", "quattuornonagintaquadringentillion",
  "quinnonagintaquadringentillion", "senonagintaquadringentillion",
  "septenonagintaquadringentillion", "octononagintaquadringentillion",
  "novenonagintaquadringentillion", "quingentillion", "unquingentillion",
  "duoquingentillion", "tresquingentillion", "quattuorquingentillion",
  "quinquingentillion", "sesquingentillion", "septenquingentillion",
  "octoquingentillion", "novenquingentillion", "deciquingentillion",
  "undeciquingentillion", "duodeciquingentillion", "tredeciquingentillion",
  "quattuordeciquingentillion", "quindeciquingentillion", "sedeciquingentillion",
  "septendeciquingentillion", "octodeciquingentillion", "novendeciquingentillion",
  "vigintiquingentillion", "unvigintiquingentillion", "duovigintiquingentillion",
  "tresvigintiquingentillion", "quattuorvigintiquingentillion",
  "quinvigintiquingentillion", "sesvigintiquingentillion", "septemvigintiquingentillion",
  "octovigintiquingentillion", "novemvigintiquingentillion", "trigintaquingentillion",
  "untrigintaquingentillion", "duotrigintaquingentillion", "trestrigintaquingentillion",
  "quattuortrigintaquingentillion", "quintrigintaquingentillion",
  "sestrigintaquingentillion", "septentrigintaquingentillion",
  "octotrigintaquingentillion", "noventrigintaquingentillion",
  "quadragintaquingentillion", "unquadragintaquingentillion", "duoquadragintaquingentillion",
  "tresquadragintaquingentillion", "quattuorquadragintaquingentillion",
  "quinquadragintaquingentillion", "sesquadragintaquingentillion",
  "septenquadragintaquingentillion", "octoquadragintaquingentillion",
  "novenquadragintaquingentillion", "quinquagintaquingentillion",
  "unquinquagintaquingentillion", "duoquinquagintaquingentillion",
  "tresquinquagintaquingentillion", "quattuorquinquagintaquingentillion",
  "quinquinquagintaquingentillion", "sesquinquagintaquingentillion",
  "septenquinquagintaquingentillion", "octoquinquagintaquingentillion",
  "novenquinquagintaquingentillion", "sexagintaquingentillion",
  "unsexagintaquingentillion", "duosexagintaquingentillion", "tresexagintaquingentillion",
  "quattuorsexagintaquingentillion", "quinsexagintaquingentillion",
  "sesexagintaquingentillion", "septensexagintaquingentillion",
  "octosexagintaquingentillion", "novensexagintaquingentillion",
  "septuagintaquingentillion", "unseptuagintaquingentillion", "duoseptuagintaquingentillion",
  "treseptuagintaquingentillion", "quattuorseptuagintaquingentillion",
  "quinseptuagintaquingentillion", "seseptuagintaquingentillion",
  "septenseptuagintaquingentillion", "octoseptuagintaquingentillion",
  "novenseptuagintaquingentillion", "octogintaquingentillion",
  "unoctogintaquingentillion", "duooctogintaquingentillion", "tresoctogintaquingentillion",
  "quattuoroctogintaquingentillion", "quinoctogintaquingentillion",
  "sexoctogintaquingentillion", "septemoctogintaquingentillion",
  "octooctogintaquingentillion", "novemoctogintaquingentillion",
  "nonagintaquingentillion", "unnonagintaquingentillion", "duononagintaquingentillion",
  "trenonagintaquingentillion", "quattuornonagintaquingentillion",
  "quinnonagintaquingentillion", "senonagintaquingentillion", "septenonagintaquingentillion",
  "octononagintaquingentillion", "novenonagintaquingentillion",
  "sescentillion", "unsescentillion", "duosescentillion", "tresescentillion",
  "quattuorsescentillion", "quinsescentillion", "sesescentillion",
  "septensescentillion", "octosescentillion", "novensescentillion",
  "decisescentillion", "undecisescentillion", "duodecisescentillion",
  "tredecisescentillion", "quattuordecisescentillion", "quindecisescentillion",
  "sedecisescentillion", "septendecisescentillion", "octodecisescentillion",
  "novendecisescentillion", "vigintisescentillion", "unvigintisescentillion",
  "duovigintisescentillion", "tresvigintisescentillion", "quattuorvigintisescentillion",
  "quinvigintisescentillion", "sesvigintisescentillion", "septemvigintisescentillion",
  "octovigintisescentillion", "novemvigintisescentillion", "trigintasescentillion",
  "untrigintasescentillion", "duotrigintasescentillion", "trestrigintasescentillion",
  "quattuortrigintasescentillion", "quintrigintasescentillion",
  "sestrigintasescentillion", "septentrigintasescentillion", "octotrigintasescentillion",
  "noventrigintasescentillion", "quadragintasescentillion", "unquadragintasescentillion",
  "duoquadragintasescentillion", "tresquadragintasescentillion",
  "quattuorquadragintasescentillion", "quinquadragintasescentillion",
  "sesquadragintasescentillion", "septenquadragintasescentillion",
  "octoquadragintasescentillion", "novenquadragintasescentillion",
  "quinquagintasescentillion", "unquinquagintasescentillion", "duoquinquagintasescentillion",
  "tresquinquagintasescentillion", "quattuorquinquagintasescentillion",
  "quinquinquagintasescentillion", "sesquinquagintasescentillion",
  "septenquinquagintasescentillion", "octoquinquagintasescentillion",
  "novenquinquagintasescentillion", "sexagintasescentillion", "unsexagintasescentillion",
  "duosexagintasescentillion", "tresexagintasescentillion", "quattuorsexagintasescentillion",
  "quinsexagintasescentillion", "sesexagintasescentillion", "septensexagintasescentillion",
  "octosexagintasescentillion", "novensexagintasescentillion",
  "septuagintasescentillion", "unseptuagintasescentillion", "duoseptuagintasescentillion",
  "treseptuagintasescentillion", "quattuorseptuagintasescentillion",
  "quinseptuagintasescentillion", "seseptuagintasescentillion",
  "septenseptuagintasescentillion", "octoseptuagintasescentillion",
  "novenseptuagintasescentillion", "octogintasescentillion", "unoctogintasescentillion",
  "duooctogintasescentillion", "tresoctogintasescentillion", "quattuoroctogintasescentillion",
  "quinoctogintasescentillion", "sexoctogintasescentillion", "septemoctogintasescentillion",
  "octooctogintasescentillion", "novemoctogintasescentillion",
  "nonagintasescentillion", "unnonagintasescentillion", "duononagintasescentillion",
  "trenonagintasescentillion", "quattuornonagintasescentillion",
  "quinnonagintasescentillion", "senonagintasescentillion", "septenonagintasescentillion",
  "octononagintasescentillion", "novenonagintasescentillion", "septingentillion",
  "unseptingentillion", "duoseptingentillion", "treseptingentillion",
  "quattuorseptingentillion", "quinseptingentillion", "seseptingentillion",
  "septenseptingentillion", "octoseptingentillion", "novenseptingentillion",
  "deciseptingentillion", "undeciseptingentillion", "duodeciseptingentillion",
  "tredeciseptingentillion", "quattuordeciseptingentillion", "quindeciseptingentillion",
  "sedeciseptingentillion", "septendeciseptingentillion", "octodeciseptingentillion",
  "novendeciseptingentillion", "vigintiseptingentillion", "unvigintiseptingentillion",
  "duovigintiseptingentillion", "tresvigintiseptingentillion",
  "quattuorvigintiseptingentillion", "quinvigintiseptingentillion",
  "sesvigintiseptingentillion", "septemvigintiseptingentillion",
  "octovigintiseptingentillion", "novemvigintiseptingentillion",
  "trigintaseptingentillion", "untrigintaseptingentillion", "duotrigintaseptingentillion",
  "trestrigintaseptingentillion", "quattuortrigintaseptingentillion",
  "quintrigintaseptingentillion", "sestrigintaseptingentillion",
  "septentrigintaseptingentillion", "octotrigintaseptingentillion",
  "noventrigintaseptingentillion", "quadragintaseptingentillion",
  "unquadragintaseptingentillion", "duoquadragintaseptingentillion",
  "tresquadragintaseptingentillion", "quattuorquadragintaseptingentillion",
  "quinquadragintaseptingentillion", "sesquadragintaseptingentillion",
  "septenquadragintaseptingentillion", "octoquadragintaseptingentillion",
  "novenquadragintaseptingentillion", "quinquagintaseptingentillion",
  "unquinquagintaseptingentillion", "duoquinquagintaseptingentillion",
  "tresquinquagintaseptingentillion", "quattuorquinquagintaseptingentillion",
  "quinquinquagintaseptingentillion", "sesquinquagintaseptingentillion",
  "septenquinquagintaseptingentillion", "octoquinquagintaseptingentillion",
  "novenquinquagintaseptingentillion", "sexagintaseptingentillion",
  "unsexagintaseptingentillion", "duosexagintaseptingentillion",
  "tresexagintaseptingentillion", "quattuorsexagintaseptingentillion",
  "quinsexagintaseptingentillion", "sesexagintaseptingentillion",
  "septensexagintaseptingentillion", "octosexagintaseptingentillion",
  "novensexagintaseptingentillion", "septuagintaseptingentillion",
  "unseptuagintaseptingentillion", "duoseptuagintaseptingentillion",
  "treseptuagintaseptingentillion", "quattuorseptuagintaseptingentillion",
  "quinseptuagintaseptingentillion", "seseptuagintaseptingentillion",
  "septenseptuagintaseptingentillion", "octoseptuagintaseptingentillion",
  "novenseptuagintaseptingentillion", "octogintaseptingentillion",
  "unoctogintaseptingentillion", "duooctogintaseptingentillion",
  "tresoctogintaseptingentillion", "quattuoroctogintaseptingentillion",
  "quinoctogintaseptingentillion", "sexoctogintaseptingentillion",
  "septemoctogintaseptingentillion", "octooctogintaseptingentillion",
  "novemoctogintaseptingentillion", "nonagintaseptingentillion",
  "unnonagintaseptingentillion", "duononagintaseptingentillion",
  "trenonagintaseptingentillion", "quattuornonagintaseptingentillion",
  "quinnonagintaseptingentillion", "senonagintaseptingentillion",
  "septenonagintaseptingentillion", "octononagintaseptingentillion",
  "novenonagintaseptingentillion", "octingentillion", "unoctingentillion",
  "duooctingentillion", "tresoctingentillion", "quattuoroctingentillion",
  "quinoctingentillion", "sexoctingentillion", "septemoctingentillion",
  "octooctingentillion", "novemoctingentillion", "decioctingentillion",
  "undecioctingentillion", "duodecioctingentillion", "tredecioctingentillion",
  "quattuordecioctingentillion", "quindecioctingentillion", "sedecioctingentillion",
  "septendecioctingentillion", "octodecioctingentillion", "novendecioctingentillion",
  "vigintioctingentillion", "unvigintioctingentillion", "duovigintioctingentillion",
  "tresvigintioctingentillion", "quattuorvigintioctingentillion",
  "quinvigintioctingentillion", "sesvigintioctingentillion", "septemvigintioctingentillion",
  "octovigintioctingentillion", "novemvigintioctingentillion",
  "trigintaoctingentillion", "untrigintaoctingentillion", "duotrigintaoctingentillion",
  "trestrigintaoctingentillion", "quattuortrigintaoctingentillion",
  "quintrigintaoctingentillion", "sestrigintaoctingentillion",
  "septentrigintaoctingentillion", "octotrigintaoctingentillion",
  "noventrigintaoctingentillion", "quadragintaoctingentillion",
  "unquadragintaoctingentillion", "duoquadragintaoctingentillion",
  "tresquadragintaoctingentillion", "quattuorquadragintaoctingentillion",
  "quinquadragintaoctingentillion", "sesquadragintaoctingentillion",
  "septenquadragintaoctingentillion", "octoquadragintaoctingentillion",
  "novenquadragintaoctingentillion", "quinquagintaoctingentillion",
  "unquinquagintaoctingentillion", "duoquinquagintaoctingentillion",
  "tresquinquagintaoctingentillion", "quattuorquinquagintaoctingentillion",
  "quinquinquagintaoctingentillion", "sesquinquagintaoctingentillion",
  "septenquinquagintaoctingentillion", "octoquinquagintaoctingentillion",
  "novenquinquagintaoctingentillion", "sexagintaoctingentillion",
  "unsexagintaoctingentillion", "duosexagintaoctingentillion",
  "tresexagintaoctingentillion", "quattuorsexagintaoctingentillion",
  "quinsexagintaoctingentillion", "sesexagintaoctingentillion",
  "septensexagintaoctingentillion", "octosexagintaoctingentillion",
  "novensexagintaoctingentillion", "septuagintaoctingentillion",
  "unseptuagintaoctingentillion", "duoseptuagintaoctingentillion",
  "treseptuagintaoctingentillion", "quattuorseptuagintaoctingentillion",
  "quinseptuagintaoctingentillion", "seseptuagintaoctingentillion",
  "septenseptuagintaoctingentillion", "octoseptuagintaoctingentillion",
  "novenseptuagintaoctingentillion", "octogintaoctingentillion",
  "unoctogintaoctingentillion", "duooctogintaoctingentillion",
  "tresoctogintaoctingentillion", "quattuoroctogintaoctingentillion",
  "quinoctogintaoctingentillion", "sexoctogintaoctingentillion",
  "septemoctogintaoctingentillion", "octooctogintaoctingentillion",
  "novemoctogintaoctingentillion", "nonagintaoctingentillion",
  "unnonagintaoctingentillion", "duononagintaoctingentillion",
  "trenonagintaoctingentillion", "quattuornonagintaoctingentillion",
  "quinnonagintaoctingentillion", "senonagintaoctingentillion",
  "septenonagintaoctingentillion", "octononagintaoctingentillion",
  "novenonagintaoctingentillion", "nongentillion", "unnongentillion",
  "duonongentillion", "trenongentillion", "quattuornongentillion",
  "quinnongentillion", "senongentillion", "septenongentillion",
  "octonongentillion", "novenongentillion", "decinongentillion",
  "undecinongentillion", "duodecinongentillion", "tredecinongentillion",
  "quattuordecinongentillion", "quindecinongentillion", "sedecinongentillion",
  "septendecinongentillion", "octodecinongentillion", "novendecinongentillion",
  "vigintinongentillion", "unvigintinongentillion", "duovigintinongentillion",
  "tresvigintinongentillion", "quattuorvigintinongentillion", "quinvigintinongentillion",
  "sesvigintinongentillion", "septemvigintinongentillion", "octovigintinongentillion",
  "novemvigintinongentillion", "trigintanongentillion", "untrigintanongentillion",
  "duotrigintanongentillion", "trestrigintanongentillion", "quattuortrigintanongentillion",
  "quintrigintanongentillion", "sestrigintanongentillion", "septentrigintanongentillion",
  "octotrigintanongentillion", "noventrigintanongentillion", "quadragintanongentillion",
  "unquadragintanongentillion", "duoquadragintanongentillion",
  "tresquadragintanongentillion", "quattuorquadragintanongentillion",
  "quinquadragintanongentillion", "sesquadragintanongentillion",
  "septenquadragintanongentillion", "octoquadragintanongentillion",
  "novenquadragintanongentillion", "quinquagintanongentillion",
  "unquinquagintanongentillion", "duoquinquagintanongentillion",
  "tresquinquagintanongentillion", "quattuorquinquagintanongentillion",
  "quinquinquagintanongentillion", "sesquinquagintanongentillion",
  "septenquinquagintanongentillion", "octoquinquagintanongentillion",
  "novenquinquagintanongentillion", "sexagintanongentillion", "unsexagintanongentillion",
  "duosexagintanongentillion", "tresexagintanongentillion", "quattuorsexagintanongentillion",
  "quinsexagintanongentillion", "sesexagintanongentillion", "septensexagintanongentillion",
  "octosexagintanongentillion", "novensexagintanongentillion",
  "septuagintanongentillion", "unseptuagintanongentillion", "duoseptuagintanongentillion",
  "treseptuagintanongentillion", "quattuorseptuagintanongentillion",
  "quinseptuagintanongentillion", "seseptuagintanongentillion",
  "septenseptuagintanongentillion", "octoseptuagintanongentillion",
  "novenseptuagintanongentillion", "octogintanongentillion", "unoctogintanongentillion",
  "duooctogintanongentillion", "tresoctogintanongentillion", "quattuoroctogintanongentillion",
  "quinoctogintanongentillion", "sexoctogintanongentillion", "septemoctogintanongentillion",
  "octooctogintanongentillion", "novemoctogintanongentillion",
  "nonagintanongentillion", "unnonagintanongentillion", "duononagintanongentillion",
  "trenonagintanongentillion", "quattuornonagintanongentillion",
  "quinnonagintanongentillion", "senonagintanongentillion", "septenonagintanongentillion",
  "octononagintanongentillion", "novenonagintanongentillion"
)

# These are meant to work with `english_fractional()`. This provides nice names
# for fractions `x / y` for `x = 1:8`, `y = 1:9` (e.g. `1 / 2` -> "one half").
# We match these names to the output of `format_fractional()`, to account for
# different levels of precision. For example:
# - 1 digit precision:  `0.3`   -> "one third"
# - 2 digits precision: `0.33`  -> "one third", `0.3` -> "one tenth"
# - 3 digits precision: `0.333` -> "one third", `0.33` -> "thirty-three hundredths"
#
# The `one` argument should be `1` or `bignum::bigfloat(1)`, depending on whether
# we're formatting a numeric vector or a bigfloat
get_english_fractions <- function(one = 1) {
  fractionals <- c(
    1 / (one * 2),
    1:2 / (one * 3),
    c(1, 3) / (one * 4),
    1:4 / (one * 5),
    c(1, 5) / (one * 6),
    1:6 / (one * 7),
    c(1, 3, 5, 7) / (one * 8),
    one * c(1, 2, 4, 5, 7, 9) / (one * 9)
  )
  english_fractionals <- c(
    "one half", "one third", "two thirds", "one quarter", "three quarters",
    "one fifth", "two fifths", "three fifths", "four fifths", "one sixth",
     "five sixths", "one seventh", "two sevenths", "three sevenths",
     "four sevenths", "five sevenths", "six sevenths", "one eigth",
     "three eigths", "five eigths", "seven eigths", "one ninth", "two ninths",
     "four ninths", "five ninths", "seven ninths", "eight ninths"
  )

  # In some cases we won't have enough precision to represent a fraction, in
  # which case `formatted == ""` and we drop that from the english fractions.
  formatted <- format_fractional(fractionals)
  names(english_fractionals) <- formatted
  english_fractionals[formatted != ""]
}

# illions ----------------------------------------------------------------------

english_illions <- function(thousands_powers) {
  out <- character(length(thousands_powers))

  illions <- thousands_powers > 0
  out[illions] <- english_illions_recursive(thousands_powers[illions])
  out
}

english_illions_recursive <- function(thousands_powers) {
  out <- character(length(thousands_powers))

  zero_powers <- thousands_powers == 0
  if (all(zero_powers)) {
    return(out)
  }

  small <- !zero_powers & thousands_powers <= 1000
  large <- !(zero_powers | small)

  out[small] <- english_hundred_illions(thousands_powers[small])
  out[large] <- paste0(
    sub("on$", "", english_illions_recursive(((thousands_powers[large] - 1) %/% 1000) + 1)),
    english_hundred_nillions(((thousands_powers[large] - 1) %% 1000) + 1)
  )
  out
}

english_hundred_illions <- function(thousands_powers) {
  english$illions[thousands_powers]
}

english_hundred_nillions <- function(thousands_powers) {
  out <- english$illions[thousands_powers]
  out[thousands_powers == 1] <- "nillion"
  out
}

# tenillions -------------------------------------------------------------------

english_tenillions <- function(tens_power) {
  illions <- english_illions(tens_power %/% 3)
  trimws(paste(c("", "ten", "hundred")[(tens_power %% 3) + 1], illions))
}

# natural numbers --------------------------------------------------------------
# - `naturals` is expected to be a non-zero positive integer-ish number

# Covers naturals 1-999
english_hundreds <- function(naturals, suffix = "") {
  # `as.integer()` allows <bignum_biginteger> to be used as an index
  # - required because `letters[bignum::biginteger(1)]` is `NA` not "a"
  # - `naturals` is always going to be between 0-999, so no precision issues
  paste0(english$hundreds[as.integer(naturals + 1L)], suffix)
}

# Covers the natural numbers (excluding zero)
english_naturals <- function(naturals, and = FALSE, hyphenate = TRUE) {
  out <- english_naturals_recursive(
    naturals = naturals,
    prefixes = character(length(naturals)),
    iteration = 1L
  )
  after_format(trimws(out), and = and, hyphenate = hyphenate)
}

english_naturals_recursive <- function(naturals, prefixes, iteration) {

  nonzero_naturals <- naturals != 0
  if (!any(nonzero_naturals)) {
    return(prefixes)
  }

  # We're only going to add prefixes whenever the 100's are empty. Otherwise we
  # get `1,000,000` -> "one million thousand", but we just want "one million".
  hundreds <- get_hundreds(naturals[nonzero_naturals])
  nonzero_hundreds <- hundreds != 0

  prefixes[nonzero_naturals][nonzero_hundreds] <- paste(
    english_hundreds(
      naturals = hundreds[nonzero_hundreds],
      suffix = get_english_suffix(iteration)
    ),
    prefixes[nonzero_naturals][nonzero_hundreds]
  )
  naturals <- consume_hundreds(naturals)
  english_naturals_recursive(naturals, prefixes, iteration = iteration + 1L)
}

get_english_suffix <- function(iteration) {
  if (iteration > length(english$suffixes)) {
    # When `iteration == 2L` we're at the thousands place, whereas
    # `english_illions(2L)` is a "million".
    paste0(" ", english_illions(iteration - 1L)) # nocov
  } else {
    english$suffixes[iteration]
  }
}

# This will raise warnings about precision issues for large numbers, which is
# now what we want since we can steer users towards {bignum} if they need more
# precision. E.g. try `get_hundreds(100^100)`.
get_hundreds <- function(naturals) {
  naturals %% 1000L
}

consume_hundreds <- function(naturals) {
  naturals %/% 1000L
}

# fractional numbers -----------------------------------------------------------
# - `fractional_characters` is the output of `format_fractional(<numeric>)`
#   where <numeric> is in range (0, 1)
# - `doubles` is expected to be a non-zero positive numeric

english_fractionals <- function(fractionals, ...) {
  UseMethod("english_fractionals")
}

# Covers numbers in range (0, 1)
english_fractionals.numeric <- function(
    fractionals,
    zero = "zero",
    and = FALSE,
    hyphenate = TRUE,
    english_fractions = get_english_fractions(1),
    ...
  ) {

  out <- character(length(fractionals))

  # The number of "english" decimal places is dependent on the number of decimals
  # shown by `format_fractional()` (as called by `format_number()`). This ensures
  # that "what you see is what you get".
  fractional_characters <- format_fractional(fractionals)
  n_decimals <- nchar(fractional_characters)

  # `zeros` occur when we don't have precision to represent small `fractionals`
  zeros <- n_decimals == 0
  nices <- fractional_characters %in% names(english_fractions)

  out[zeros] <- zero
  out[nices] <- english_fractions[fractional_characters[nices]]

  if (all(zeros | nices)) {
    return(out)
  }

  fracs <- !zeros & !nices

  # `format_fractional()` gives us the trailing digits (e.g. 0.0123 -> "0123")
  # so we can coerce this to numeric to get the natural number representation.
  natural_fracs <- as.double(fractional_characters[fracs])

  # NOTE: We may have to trim leading zeros if they cause an issue
  # natural_fracs <- as.double(sub("^0+", "", fractional_characters[fracs]))

  out[fracs] <- paste0(
    english_naturals(natural_fracs, and = and, hyphenate = hyphenate),
    " ",
    if (hyphenate) sub(" ", "-", english_tenillions(n_decimals[fracs])) else english_tenillions(n_decimals[fracs]),
    # "one thousandth" for "0.001" vs. "two thousandths" for "0.002"
    ifelse(grepl("^0*1$", fractional_characters[fracs]), "th", "ths")
  )
  out
}

english_fractionals.bignum_bigfloat <- function(
    fractionals,
    zero = "zero",
    and = FALSE,
    hyphenate = TRUE,
    english_fractions = get_english_fractions(bignum::bigfloat("1")),
    ...
  ) {

  out <- character(length(fractionals))

  # The number of "english" decimal places is dependent on the number of decimals
  # shown by `format_fractional()` (as called by `format_number()`). This ensures
  # that "what you see is what you get".
  fractional_characters <- format_fractional(fractionals)
  n_decimals <- nchar(fractional_characters)

  # `zeros` occur when we don't have enough precision to represent small `fractionals`
  zeros <- n_decimals == 0
  nices <- fractional_characters %in% names(english_fractions)

  out[zeros] <- zero
  out[nices] <- english_fractions[fractional_characters[nices]]

  if (all(zeros | nices)) {
    return(out)
  }

  fracs <- !zeros & !nices

  # `format_fractional()` gives us the trailing digits (e.g. 0.0123 -> "0123")
  # so we can give them to the `bignum::biginteger(<character>)` constructor
  natural_fracs <- bignum::biginteger(fractional_characters[fracs])

  # NOTE: We may have to trim leading zeros if they cause an issue
  # natural_fracs <- bignum::biginteger(sub("^0+", "", fractional_characters[fracs]))

  out[fracs] <- paste0(
    english_naturals(natural_fracs, and = and, hyphenate = hyphenate),
    " ",
    if (hyphenate) sub(" ", "-", english_tenillions(n_decimals[fracs])) else english_tenillions(n_decimals[fracs]),
    # "one thousandth" for "0.001" vs. "two thousandths" for "0.002"
    ifelse(grepl("(0|\\.)1$", fractional_characters[fracs]), "th", "ths")
  )
  out
}

# formatters -------------------------------------------------------------------
# - `english_naturals` is the output of `english_naturals()`

# Controls all post-englishification formatting of the natural numbers
after_format <- function(english_naturals, and = FALSE, hyphenate = TRUE) {
  if (and) english_naturals <- andify(english_naturals)
  if (!hyphenate) english_naturals <- unhypenate(english_naturals)
  english_naturals
}

# Add an "and" before the last number if in 1:99 (e.g. "one thousand and one"
# and not "one thousand and one hundred")
andify <- function(english_naturals) {
  last_number <- sub(".*\\s", "", english_naturals)
  needs_an_and <- last_number %in% english$hundreds[1:99 + 1]

  english_naturals[needs_an_and] <- sub(
    pattern = "^(.*) (\\S+)$",
    replacement =  "\\1 and \\2",
    x = english_naturals[needs_an_and]
  )
  english_naturals
}

unhypenate <- function(english_naturals) {
  sub("-", " ", english_naturals)
}