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When the sum of a number's factors less than itself is equal to that number, it is called a perfect number. The lowest perfect number is 6 (1 + 2 + 3 = 6), and the third lowest perfect number is 496 (1 + 2 + 4 + 8 + 16 + 31 + 62 + 124 + 248 = 496). See if you can find the second lowest perfect number.

24

28. the factors of which are 1 + 2 + 4 + 7 + 14, which equals 28?

28 (1+2+4+7+14)

then 496 followed by

8128 - (1 + 2 + 4 + 8 + 16 + 32 + 64 + 127 + 254 + 508 + 1016
+ 2032 + 4064)

Good answer given by you my friend.