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deficient number

American  

noun

Mathematics.

  1. a positive number that is greater than the sum of all positive integers that are submultiples of it, as 10, which is greater than the sum of 1, 2, and 5.

Etymology

Origin of deficient number

First recorded in 1720–30

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.