Yeh has two separate but related numeral systems: A traditional vigesimal (base-20) system, and a modern decimal (base-10) system.
Yeh also uses two written numeral systems: Indigenous logorams are used represent vigesimal numerals, while Arabic numerals are used to write in decimal.
In the past, vigesimal numerals were the standard for denoting numbers in Yeh. But in the last few centuries, the use of vigesimal has been replaced by a decimal system for most applications. Decimal is the standard for scientific measurement, accounting, and everyday use. The traditional vigesimal system continues to be used in sequel titles, in tattoos, for ceremonial purposes, and as a formal way to record dates.
Specific words are used to render the digits zero through twenty.
Numerals for 21-39 are formed starting with "yau" (twenty), followed by the conjunction "na," and ending with the remaining digit.
For 0-399, multiples of 20 are expressed as "yau" followed by a multiplier digit. Digits in the ones position are preceded by the conjunction "na."
Numerals 400-7999 are formed starting with the word ómhwe (four hundred), followed by a multiplier digit, and then any remaning digits in the twenties and ones position.
The pattern continues indefinitely: Numerals consist of specific words, representing powers of 20, followed by a multiplier digit, said in descending order. In compound numerals, digits in the ones position are preceded by the conjunction "na."
Yeh vigesimal numerals are written right to left using positional notation. Below are the written forms of numbers 1-20.
Converted decimal value included below each sample, for comparison.
An example of a large numeral:
When counting in decimal, numbers 0-29 are denoted identically to their vigesimal counterparts.
Values in the tens position equal to 30 and above are rendered as "prainy" followed by a multiplier ("tómva" through "ngë́ri"). Digits in the ones position are restricted to 1-9 ("i" through "ngë́ri") and are preceded by the conjunction "na."
Subsequent powers of 10 are expressed with specific words, and also followed by a multiplier digit ("rah" through "ngë́ri") if applicable.
Arabic numerals are used to write decimal Yeh numerals.
Ordinals are formed with the suffix "-mento." See Derivational Operations.