56716821 has 16 divisors (see below), whose sum is σ = 96028800. Its totient is φ = 32409504.

The previous prime is 56716813. The next prime is 56716841. The reversal of 56716821 is 12861765.

56716821 is a `hidden beast` number, since 567 + 16 + 82 + 1 = 666.

56716821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 56716821 - 2³ = 56716813 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56716801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149856 + ... + 150233.

It is an arithmetic number, because the mean of its divisors is an integer number (6001800).

Almost surely, 2^56716821 is an apocalyptic number.

It is an amenable number.

56716821 is a deficient number, since it is larger than the sum of its proper divisors (39311979).

56716821 is a wasteful number, since it uses less digits than its factorization.

56716821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300105 (or 300099 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 56716821 is about 7531.0570971146. The cubic root of 56716821 is about 384.2117362553.

The spelling of 56716821 in words is "fifty-six million, seven hundred sixteen thousand, eight hundred twenty-one".