56521831 has 2 divisors, whose sum is σ = 56521832. Its totient is φ = 56521830.

The previous prime is 56521811. The next prime is 56521837. The reversal of 56521831 is 13812565.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 56521831 - 2⁵ = 56521799 is a prime.

It is a super-2 number, since 2×56521831² = 6389434759185122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 56521793 and 56521802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56521837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28260915 + 28260916.

It is an arithmetic number, because the mean of its divisors is an integer number (28260916).

Almost surely, 2^56521831 is an apocalyptic number.

56521831 is a deficient number, since it is larger than the sum of its proper divisors (1).

56521831 is an equidigital number, since it uses as much as digits as its factorization.

56521831 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 31.

The square root of 56521831 is about 7518.1002254559. The cubic root of 56521831 is about 383.7709295492.

The spelling of 56521831 in words is "fifty-six million, five hundred twenty-one thousand, eight hundred thirty-one".