Cyrillic numerals

Cyrillic numerals are a numeral system derived from the Cyrillic script, developed in the First Bulgarian Empire in the late 10th century. It was used in the First Bulgarian Empire and by South and East Slavic peoples. The system was used in Russia as late as the early 18th century, when Peter the Great replaced it with Arabic numerals as part of his civil script reform initiative. Cyrillic numbers played a role in Peter the Great's currency reform plans, too, with silver wire kopecks issued after 1696 and mechanically minted coins issued between 1700 and 1722 inscribed with the date using Cyrillic numerals. By 1725, Russian Imperial coins had transitioned to Arabic numerals. The Cyrillic numerals may still be found in books written in the Church Slavonic language.

The system is a quasi-decimal alphabetic system, equivalent to the Ionian numeral system but written with the corresponding graphemes of the Cyrillic script. The order is based on the original Greek alphabet rather than the standard Cyrillic alphabetical order.

A separate letter is assigned to each unit (1, 2, ... 9), each multiple of ten (10, 20, ... 90), and each multiple of one hundred (100, 200, ... 900). To distinguish numbers from text, a titlo (   ҃ ) is sometimes drawn over the numbers, or they are set apart with dots. The numbers are written as pronounced in Slavonic, generally from the high value position to the low value position, with the exception of 11 through 19, which are written and pronounced with the ones unit before the tens; for example, ЗІ (17) is "семнадсять" (literally seven-on-ten, cf. the English seven-teen).

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