Numeral systems by culture  

HinduArabic numerals  
Eastern Arabic Indian family Khmer 
Mongolian Thai Western Arabic 
East Asian numerals  
Chinese Counting rods Japanese 
Korean Suzhou 
Alphabetic numerals  
Abjad Armenian Āryabhaṭa Cyrillic 
Ge'ez Greek (Ionian) Hebrew 
Other systems  
Attic Babylonian Brahmi Egyptian Etruscan Inuit 
Mayan Quipu Roman Urnfield 
List of numeral system topics  
Positional systems by base  
Decimal (10)  
1, 2, 3, 4, 5, 8, 12, 16, 20, 60 more…  
A septemvigesimal numeral system has a base of twentyseven. It is used in two natural languages, the Telefol language and the Oksapmin language of Papua New Guinea.
Septemvigesimal notation can be used as a concise representation of ternary data, where each septemvigesimal digit represents three ternary digits. This is similar to using octal notation to represent binary data, though the digit set is closer in size to hexadecimal.
Examples: (Digits 10–26 are represented by letters A through Q.)
Decimal  Ternary  Septemvigesimal 

0  000  0 
1  001  1 
2  002  2 
3  010  3 
5  012  5 
10  101  A 
15  120  F 
20  202  K 
25  221  P 
26  222  Q 
27  1000  10 
81  10000  30 
An alternate encoding, mapping 0 to space and 1–26 to A–Z, is occasionally used in puzzles to transform ternary triplets into words or messages.
