56615056661 has 2 divisors, whose sum is σ = 56615056662. Its totient is φ = 56615056660.

The previous prime is 56615056639. The next prime is 56615056691. The reversal of 56615056661 is 16665051665.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41010300100 + 15604756561 = 202510^2 + 124919^2 .

It is a cyclic number.

It is not a de Polignac number, because 56615056661 - 2¹⁸ = 56614794517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56615056691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28307528330 + 28307528331.

It is an arithmetic number, because the mean of its divisors is an integer number (28307528331).

Almost surely, 2^56615056661 is an apocalyptic number.

It is an amenable number.

56615056661 is a deficient number, since it is larger than the sum of its proper divisors (1).

56615056661 is an equidigital number, since it uses as much as digits as its factorization.

56615056661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972000, while the sum is 47.

The spelling of 56615056661 in words is "fifty-six billion, six hundred fifteen million, fifty-six thousand, six hundred sixty-one".