Difference between revisions of "Abundant number"

(Examples)
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==Properties==
 
==Properties==
 
There are infinitely many abundant numbers.
 
There are infinitely many abundant numbers.
 
 
Every positive multiple of an abundant number is an abundant number.
 
Every positive multiple of an abundant number is an abundant number.
 
 
Every multiple of a perfect number greater than itself is an abundant number.
 
Every multiple of a perfect number greater than itself is an abundant number.
  

Revision as of 20:08, 6 February 2018

An abundant number is a number $n$ for which the sum of its proper divisors is greater than $n$ itself. For example, 12 is abundant because the sum of its proper divisors is 1 + 2 + 3 + 4 + 6 = 16 > 12.

Examples

The first 10 abundant numbers are:

12, 18, 20, 24, 30, 36, 40, 42, 48, 54,...

The first 10 odd abundant numbers are:

945, 1575, 2205, 2835, 3465, 4095, 4725, 5355, 5775, 5985,...

Properties

There are infinitely many abundant numbers. Every positive multiple of an abundant number is an abundant number. Every multiple of a perfect number greater than itself is an abundant number.

See also

Perfect number

Deficient number