56756781 has 36 divisors (see below), whose sum is σ = 89867232. Its totient is φ = 35790984.

The previous prime is 56756773. The next prime is 56756789. The reversal of 56756781 is 18765765.

56756781 is a `hidden beast` number, since 5 + 6 + 7 + 567 + 81 = 666.

It is an interprime number because it is at equal distance from previous prime (56756773) and next prime (56756789).

It is not a de Polignac number, because 56756781 - 2³ = 56756773 is a prime.

It is a super-2 number, since 2×56756781² = 6442664378963922, which contains 22 as substring.

Its product of digits (352800) is a multiple of the sum of its prime factors (700).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56756789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 87400 + ... + 88046.

It is an arithmetic number, because the mean of its divisors is an integer number (2496312).

Almost surely, 2^56756781 is an apocalyptic number.

It is an amenable number.

56756781 is a deficient number, since it is larger than the sum of its proper divisors (33110451).

56756781 is an equidigital number, since it uses as much as digits as its factorization.

56756781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700 (or 669 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 56756781 is about 7533.7096439935. The cubic root of 56756781 is about 384.3019475684.

The spelling of 56756781 in words is "fifty-six million, seven hundred fifty-six thousand, seven hundred eighty-one".