uninum

http://billposer.org/Software/libuninum.html

Libuninum is a library that provides conversion in both directions between textual representations of numbers and integers. The library is written in C but provides a Tcl interface. Virtually all known number systems, living and dead, are covered:

   Aegean
   Arabic_Alphabetic
   Arabic_Persian
   Arabic_Western
   Armenian
   Balinese
   Bengali
   Burmese
   Chinese_Counting_Rod_Early
   Chinese_Counting_Rod_Late
   Chinese_Counting_Rod_Early_No_Zero
   Chinese_Counting_Rod_Late_No_Zero
   Chinese_Legal_Simplified
   Chinese_Legal_Traditional
   Chinese_Regular_Simplified
   Chinese_Regular_Traditional
   Chinese_Regular_Place
   Common_Braille
   Cyrillic
   Devanagari
   Egyptian
   Ethiopic
   Ewellic_Decimal
   Ewellic_Hexadecimal
   French_Braille
   Glagolitic
   Greek_Lower
   Greek_Upper
   Gujarati
   Gurmukhi
   Hebrew_Early
   Hebrew_Late
   Hexadecimal_Lower
   Hexadecimal_Upper
   Japanese_Regular_Simplified
   Japanese_Regular_Traditional
   Japanese_Legal_Simplified
   Japanese_Legal_Traditional
   Japanese_Western_Mixed
   Kannada
   Kayah_Li
   Kharoshthi
   Khmer
   Klingon
   Lao
   Lepcha
   Limbu
   Malayalam
   Mandarin_Legal_Simplified
   Mandarin_Legal_Traditional
   Mandarin_Regular_Simplified
   Mandarin_Regular_Traditional
   Mongolian
   Mxedruli
   New_Tai_Lue
   Nko
   Ol_Chiki
   Old_Italic
   Old_Persian
   Oriya
   Osmanya
   Phoenician
   Roman_Lower
   Roman_Upper
   Russian_Braille
   Saurashtra
   Shan
   Sinhala
   Sundanese
   Suzhou
   Tamil_Place
   Tamil_Traditional
   Telugu
   Tengwar_Decimal
   Tengwar_Duodecimal
   Thai
   Tibetan
   Vai
   Verdurian
   Western_Lower
   Western_Upper
   Xucuri_Lower
   Xucuri_Upper