abundant number

A natural number whose proper divisors sum to more than the number. For example, the proper divisors of 12 are 1, 2, 3, 4, and 6, and these add up to 16. Since 16 > 12, 12 is an abundant number. A number whose proper divisors sum to less than the number is called deficient, and one whose proper divisors sum to exactly itself is called perfect.


  • Smith, B. Sidney: author

Citation Info

  • [MLA] Smith, B. Sidney. "abundant number." Platonic Realms Interactive Mathematics Encyclopedia. Platonic Realms, 21 Feb 2013. Web. 21 Feb 2013. <>
  • [APA] Smith, B. Sidney (21 Feb 2013). abundant number. Retrieved 21 Feb 2013 from the Platonic Realms Interactive Mathematics Encyclopedia:


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