There is a formula to calculate even perfect numbers, 2p-1(2p - 1) where p is a Prime number.
When p = 7 then 26(27 - 1) = 64 x 127 = 8128
So 8128 is the 4th perfect number.
(The other three occur when p = 2, 3 and 5)
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abundant since sum of divisors is 16256
22 is not a perfect number but 6, 28, 496 and 8128 are perfect numbers.
6, 28, 496, 8128, 33550336
496, 8128, 33550336, 8589869056, 137438691328, 2305843008139952128
No, it isn't. In fact, it is not known whether are odd perfect numbers exist. The first perfect numbers are 6, 28, 496, and 8128.