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# Pseudoperfect numbers

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**Pseudoperfect numbers** are numbers for which two or more of their divisors add up to the numbers themselves. For example, 12 is pseudoperfect, since its divisors being 1, 2, 3, 4, 6, 12, we can ignore the 4 and obtain 1 + 2 + 3 + 6 = 12. See A005835 for more.

Obviously deficient numbers can't be pseudoperfect, while abundant numbers usually are (and if they are not, they are weird numbers). Technically, perfect numbers are also pseudoperfect.

All Granville numbers are pseudoperfect.