56861587621 has 2 divisors, whose sum is σ = 56861587622. Its totient is φ = 56861587620.

The previous prime is 56861587613. The next prime is 56861587633. The reversal of 56861587621 is 12678516865.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41580919396 + 15280668225 = 203914^2 + 123615^2 .

It is a cyclic number.

It is not a de Polignac number, because 56861587621 - 2³ = 56861587613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56861587681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28430793810 + 28430793811.

It is an arithmetic number, because the mean of its divisors is an integer number (28430793811).

Almost surely, 2^56861587621 is an apocalyptic number.

It is an amenable number.

56861587621 is a deficient number, since it is larger than the sum of its proper divisors (1).

56861587621 is an equidigital number, since it uses as much as digits as its factorization.

56861587621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4838400, while the sum is 55.

The spelling of 56861587621 in words is "fifty-six billion, eight hundred sixty-one million, five hundred eighty-seven thousand, six hundred twenty-one".