56561355913 has 2 divisors, whose sum is σ = 56561355914. Its totient is φ = 56561355912.

The previous prime is 56561355883. The next prime is 56561355959. The reversal of 56561355913 is 31955316565.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44534505024 + 12026850889 = 211032^2 + 109667^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56561355913 is a prime.

It is not a weakly prime, because it can be changed into another prime (56561355413) 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, 28280677956 + 28280677957.

It is an arithmetic number, because the mean of its divisors is an integer number (28280677957).

Almost surely, 2^56561355913 is an apocalyptic number.

It is an amenable number.

56561355913 is a deficient number, since it is larger than the sum of its proper divisors (1).

56561355913 is an equidigital number, since it uses as much as digits as its factorization.

56561355913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1822500, while the sum is 49.

The spelling of 56561355913 in words is "fifty-six billion, five hundred sixty-one million, three hundred fifty-five thousand, nine hundred thirteen".