perfect number

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perfect number

A positive integer that is equal to the sum of its positive integral factors, including 1 but excluding itself.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

perfect number

(Mathematics) an integer, such as 28, that is equal to the sum of all its possible factors, excluding itself
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

per′fect num′ber

a positive number that is equal to the sum of all positive integers that are submultiples of it, as 6, which is equal to the sum of 1, 2, and 3.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

per·fect number

A positive integer that equals the sum of all of its divisors other than itself. An example is 28, whose divisors (not counting itself) are 1, 2, 4, 7, and 14, which added together give 28.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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A former player and physiotherapist at the club before turning to coaching, Paisley was described as the "perfect Number Two".
The 10 other competing films are Dominik Moll's 'Only Beasts,' Amjad Abu Alala's 'You Will Die at 20,' Igort's '5 is the Perfect Number,' Fabienne Berthaud's 'A Bigger World,' Javro Bustamante's 'The Weeping Woman,' Dag Johan Haugerud's 'Beware of Children,' Jan Komasa's 'Corpus Christi,' Mattie Do's 'The Long Walk,' Manele Labidi Labbe's 'Arab Blue' and Jo Odagiri's 'They Say Nothing Stays the Same.'
Coke Studio launched a more vibrant and patriotic remake of 'Hum Ek Hain' by giving it a touch of some new lyrics which makes it a perfect number to listen and dance at.
He added: "I think three is the perfect number. It will probably be the last one, it's something we don't want to do too often.
It's a shot I've been working on on the range the last few days and it was a perfect 6-iron, it was a perfect number for me, and when it came off the bat I knew it was pretty good."
Chelsea assistant boss Gianfranco Zola says Blues boss Maurizio Sarri thought Morata could be the "perfect number nine".
The new range#6- the perfect number for your skin - is being 'tipped to rival household name beauty brands - with the discount retailer offering a complete six piece anti-ageing skincare range where every item is a [pounds sterling]1, and we want it all.
Four could turn out to be the perfect number for Furia Cruzada.
"It was the perfect number of participants with a great bond developed throughout the week.