Asked in Prime Numbers
Prime Numbers

Why is the prime number 11 not perfect?

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Answer

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Wiki User
04/27/2010

A "perfect number" is defined to be a number such that all of its factors - smaller than the number itself - add up to the number. Examples:

6 = 1 + 2 + 3

28 = 1 + 2 + 4 + 7 + 14

11 is not equal to its only factor (smaller than itself), the number 1.