A googol is the large number 10 to the 100th power. In decimal notation, it is written as the digit 1 followed by one hundred 0s:

10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.

The term was coined in 1920 by 9-year-old Milton Sirotta (1911–1981), nephew of American mathematician Edward Kasner. Kasner popularized the concept in his 1940 book Mathematics and the Imagination. Other names for googol include ten duotrigintillion on the short scale, ten thousand sexdecillion on the long scale, or ten sexdecilliard on the Peletier long scale.

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