56561688857 has 2 divisors, whose sum is σ = 56561688858. Its totient is φ = 56561688856.

The previous prime is 56561688763. The next prime is 56561688899. The reversal of 56561688857 is 75888616565.

56561688857 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49704027136 + 6857661721 = 222944^2 + 82811^2 .

It is a cyclic number.

It is not a de Polignac number, because 56561688857 - 2¹² = 56561684761 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 56561688793 and 56561688802.

It is not a weakly prime, because it can be changed into another prime (56561685857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28280844428 + 28280844429.

It is an arithmetic number, because the mean of its divisors is an integer number (28280844429).

Almost surely, 2^56561688857 is an apocalyptic number.

It is an amenable number.

56561688857 is a deficient number, since it is larger than the sum of its proper divisors (1).

56561688857 is an equidigital number, since it uses as much as digits as its factorization.

56561688857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768000, while the sum is 65.

The spelling of 56561688857 in words is "fifty-six billion, five hundred sixty-one million, six hundred eighty-eight thousand, eight hundred fifty-seven".