n is called superperfect number if σ(σ(n)) = 2n and every even superperfect number n must be a power of 2, that is, 2p −1 such that 2p − 1 is a Mersenne prime.
n is called superperfect number if σ(σ(n)) = 2n and every even superperfectnumber n must be a power of 2, that is, 2p −1 such that 2p − 1 is a Mersenneprime.