56507681 has 2 divisors, whose sum is σ = 56507682. Its totient is φ = 56507680.

The previous prime is 56507669. The next prime is 56507683. The reversal of 56507681 is 18670565.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55726225 + 781456 = 7465^2 + 884^2 .

It is a cyclic number.

It is not a de Polignac number, because 56507681 - 2⁶ = 56507617 is a prime.

It is a super-2 number, since 2×56507681² = 6386236023995522, which contains 22 as substring.

Together with 56507683, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (56507683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28253840 + 28253841.

It is an arithmetic number, because the mean of its divisors is an integer number (28253841).

Almost surely, 2^56507681 is an apocalyptic number.

It is an amenable number.

56507681 is a deficient number, since it is larger than the sum of its proper divisors (1).

56507681 is an equidigital number, since it uses as much as digits as its factorization.

56507681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 56507681 is about 7517.1591043425. The cubic root of 56507681 is about 383.7389017364.

It can be divided in two parts, 5650 and 7681, that added together give a palindrome (13331).

The spelling of 56507681 in words is "fifty-six million, five hundred seven thousand, six hundred eighty-one".