perfect number

noun

Definition of perfect number

: an integer (such as 6 or 28) the sum of whose integral factors including 1 but excluding itself is equal to itself

Recent Examples of perfect number from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'perfect number.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of perfect number

14th century


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