56309881 has 2 divisors, whose sum is σ = 56309882. Its totient is φ = 56309880.

The previous prime is 56309867. The next prime is 56309917. The reversal of 56309881 is 18890365.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46172025 + 10137856 = 6795^2 + 3184^2 .

It is a cyclic number.

It is not a de Polignac number, because 56309881 - 2⁵ = 56309849 is a prime.

It is a super-2 number, since 2×56309881² = 6341605396468322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (56309581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28154940 + 28154941.

It is an arithmetic number, because the mean of its divisors is an integer number (28154941).

Almost surely, 2^56309881 is an apocalyptic number.

It is an amenable number.

56309881 is a deficient number, since it is larger than the sum of its proper divisors (1).

56309881 is an equidigital number, since it uses as much as digits as its factorization.

56309881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 56309881 is about 7503.9910047920. The cubic root of 56309881 is about 383.2906305719.

The spelling of 56309881 in words is "fifty-six million, three hundred nine thousand, eight hundred eighty-one".