The number system of Babylon

from absolute value to place-value numbers

The figure on the left shows two numbers written in Sumerian and Babylonian notation. The first example shows the number 1859. The Sumerian notation, given in the top line, depicts it in an absolute value system by adding as many of the basic numerals as necessary to make up the final number:

600 + 600 + 600 + 50 + 9
The Babyonian notation is shown in the next line. It uses the position-value notation for the base 60:
30 (x 60) + 59 (x 1)

The second example shows the number 4818. The Sumerian representation is:

3600 + 600 + 600 + 18
The Babyonian notation requires only the pictographs for 1 and 10; all other pictographs are no longer required in place-value notation:
1 (x 602) + 20 (x 60) + 18 (x 1)

The pictographs , which can only stand for 30 in the Sumerian system, can now stand for 30, 30 x 60, 30 x 602 and any higher powers of 60. But each place usually requires several pictographs to indicate how much it contributes to the number.

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