perfect number


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

Examples of perfect number in a Sentence

Recent Examples on the Web In every conceivable way, Van Basten was the perfect number nine., 15 Aug. 2019 There was always the perfect number of raisins per slice, mostly scattered across and sometimes in greedy clumps. Zoë Sessums, Bon Appetit, 6 Apr. 2018 Roma legend Francesco Totti has described what would make his 'perfect number 10', choosing attributes from various legends of the game, past and present, to do so., 5 Sep. 2017

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.

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First Known Use of perfect number

14th century, in the meaning defined above

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The first known use of perfect number was in the 14th century

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Cite this Entry

“Perfect number.” Dictionary, Merriam-Webster, Accessed 25 Jul. 2021.

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