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# Hebrew numerals

The system of Hebrew numerals is a quasi-decimal alphabetic numeral system using the letters of the Hebrew alphabet.

In this system, there was 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 each hundreds (100, 200, ..., 900) a separate letter. Gematria (Jewish numerology) uses these transformations extensively.

Hebrew Decimal Glyph
Aleph 1 א
Bet 2 ב
Gimmel 3 ג
Dalet 4 ד
Hey 5 ה
Vav 6 ו
Zayin 7 ז
Het 8 ח
Tet 9 ט
Yod 10 י
Kaf 20 כ
Lamed 30 ל
Mem 40 מ
Nun 50 נ
Samekh 60 ס
Ayin 70 ע
Phei 80 פ
Kuf 100 ק
Resh 200 ר
Shin 300 ש
Tav 400 ת
Kaf Sofeet 500 ך
Mem Sofeet 600 ם
Nun Sofeet 700 ן
Phei Sofeet 800 ף

The alphabetic system operates on the additive principle in which the numeric values of the letters are added together to form the total. For example, 177 is represented as קעז which corresponds to 100 + 70 + 7 = 177.

The numbers 15 and 16 are represented as טו ‎(9+6) and טז ‎(9+7) respectively, instead of יה and יו. This is done in order to refrain from using the sacred combinations that are a part of the name of God in Judaism.

This system requires 27 letters, so the 22-letter Hebrew alphabet is sometimes extended to 27 by using 5 sofeet (final) forms of the Hebrew letters. Alternatively (and more often), the last letter, tav (which has the value 400) is used in combination with itself and/or other letters from qof (100) onwards, to generate numbers from 500 and above.

A gershayim mark (similar to a double quote mark) is often inserted before the last (leftmost) letter to indicate that the sequence of letters represents a number rather than a word. When only one letter is used (as for the numbers 1-9, 10, 20, etc.), a geresh mark (similar to a single quote mark) follows the letter.

Thousands are counted separately, and the thousand count precedes the rest of the number (to the right, since Hebrew is read from right to left). There are no special marks to signify that the 'count' is starting over with thousands, which theoretically can lead to ambiguity. When specifying years of the Hebrew calendar in the present millennium, writers usually omit the 'thousands' [ה]. The current Israeli coinage includes the thousands.

Modern Hebrew uses the standard decimal system for most purposes. The Hebrew numeral system is nowadays used mainly for specifying the days and years of the Hebrew calendar, for bulleted or numbered lists (instead of A, B, C, D ...), and in numerology (gematria).

### Example

"(The) 4th (day of the month of) Adar, (in the year) 5764" would be written: ד' אדר ה' תשס"ד (where 5764 = 5*1000 + 400 + 300 + 60 + 4).