56561614991 has 32 divisors (see below), whose sum is σ = 69145464960. Its totient is φ = 45163008000.

The previous prime is 56561614987. The next prime is 56561614997. The reversal of 56561614991 is 19941616565.

56561614991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 56561614991 - 2² = 56561614987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56561614997) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17133041 + ... + 17136341.

It is an arithmetic number, because the mean of its divisors is an integer number (2160795780).

Almost surely, 2^56561614991 is an apocalyptic number.

56561614991 is a deficient number, since it is larger than the sum of its proper divisors (12583849969).

56561614991 is a wasteful number, since it uses less digits than its factorization.

56561614991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4755.

The product of its digits is 1749600, while the sum is 53.

The spelling of 56561614991 in words is "fifty-six billion, five hundred sixty-one million, six hundred fourteen thousand, nine hundred ninety-one".