Hebrew numerals

The system of Hebrew numerals is a quasi-decimal alphabetic numeral system using the letters of the Hebrew alphabet. The system was adapted from that of the Greek numerals in the late 2nd century BC.

The current numeral system is also known as the Hebrew alphabetic numerals to contrast with earlier systems of writing numerals used in classical antiquity. These systems were inherited from usage in the Aramaic and Phoenician scripts, attested from c. 800 BC in the so-called Samaria ostraca and sometimes known as Hebrew-Aramaic numerals, ultimately derived from the Egyptian Hieratic numerals.

The Greek system was adopted in Hellenistic Judaism and had been in use in Greece since about the 5th century BC.

In this system, there is no notation for zero, and the numeric values for individual letters are added together. Each unit (1, 2, ..., 9) is assigned a separate letter, each tens (10, 20, ..., 90) a separate letter, and the first four hundreds (100, 200, 300, 400) a separate letter. The later hundreds (500, 600, 700, 800 and 900) are represented by the sum of two or three letters representing the first four hundreds. To represent numbers from 1,000 to 999,999, the same letters are reused to serve as thousands, tens of thousands, and hundreds of thousands. Gematria (Jewish numerology) uses these transformations extensively.

In Israel today, the decimal system of Arabic numerals (ex. 0, 1, 2, 3, etc.) is used in almost all cases (money, age, date on the civil calendar). The Hebrew numerals are used only in special cases, such as when using the Hebrew calendar, or numbering a list (similar to a, b, c, d, etc.), much as Roman numerals are used in the West.

Numbers in Hebrew from zero to one million. Hebrew alphabet are used to a limited extent to represent numbers, widely used on calendars. For other uses Arabic numerals are included. Cardinal and ordinal numbers must agree in gender with the noun they are describing. If there is no such noun (e.g. telephone numbers), the feminine form is used. For ordinal numbers greater than ten the cardinal is used and numbers above the value 20 have no gender.

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