Power of 10

There are two conventions for naming positive powers of ten, beginning with 109, called the long and short scales.

Numbers larger than about a trillion are rarely referred to by name or written out as digits, but instead are typically described with exponent notation.

The term was coined by 9-year-old Milton Sirotta, nephew of American mathematician Edward Kasner.

It was popularized in Kasner's 1940 book Mathematics and the Imagination, where it was used to compare and illustrate very large numbers.

A number written in scientific notation has a significand (sometime called a mantissa) multiplied by a power of ten.