(C)Copyright 2019, C. Burke.

So, yes, you're weird!

Weird numbers are a subset of Abundant numbers.

In brief:

A **perfect** number is one where the sum of the number's factors, excluding the number itself, equal the number. Ex: 1+2+3 = 6.

An **abundant** number is one where the sum of the number's factors, excluding the number itself, is greater than the number. Ex: 1+2+3+4+6=16 > 12.

A **semiperfect** number is one where a subset of the number's factors have a sum equal to the number. Ex: 1+2+3+6 = 12.

A perfect number is also considered to be semiperfect, unlike my wife who is perfect and I would never consider to be semiperfect.

A **weird** number is abundant but not semiperfect: there is no subset of factors that add up to the number.

Ex: no combination of 1, 2, 5, 7, 10, 14, and 35 add up to 70, but the sum of the factors is 74.

I was familiar with semiperfect, but not the "weird" term until I was looking up what the prefixes for "abundant" numbers were.

*Come back often for more funny math and geeky comics.*

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