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# Perfect number

## Question

Perfect numbers are number whose sum of factors are twice the number itself.

Example

1. 6 factors of 6 are 1,2,3 and 6 sum=12 i.e 2 * 6

2. 28 factors 1,2,4,7,14,28 sum=56 i.e 2 * 28

can you tell any other perfect no?

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1 factors 1, 1 sum =2 i.e. 2*1

Edited by TimeSpaceLightForce
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1 factors 1, 1 sum =2 i.e. 2*1

1 has only 1 as a factor so sum is 1

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Didn`t find one yet

Edited by wolfgang
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Perfect numbers are number whose sum of factors are twice the number itself.

Example

1. 6 factors of 6 are 1,2,3 and 6 sum=12 i.e 2 * 6

2. 28 factors 1,2,4,7,14,28 sum=56 i.e 2 * 28

can you tell any other perfect no?

I would rather say they are half perfect because their factors sum is twice of them. 1 is perfect.

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I am only aware of this general rule.

P = 2

p-1(2p - 1), where M = 2p - 1 is a Mersenne prime.
Example:
2*(22 - 1) = 6
22*(23 - 1) = 28
24*(25 - 1) = 496
26*(27 - 1) = 8128
etc.

That is not to say there aren't any other possibilities for finding perfect numbers.

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COMBINATION: 4927

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Perfect numbers are number whose sum of factors are twice the number itself.

Example

1. 6 factors of 6 are 1,2,3 and 6 sum=12 i.e 2 * 6

2. 28 factors 1,2,4,7,14,28 sum=56 i.e 2 * 28

can you tell any other perfect no?

I would rather say they are half perfect because their factors sum is twice of them. 1 is perfect.

In old (Euclid) times, they did not count the number as its own divisor, but they did count 1. Thus, Perfect Number used to be equal to the sum of its divisors (Aliquot Parts.)

(Don't quote me on that.)

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