56629721 has 16 divisors (see below), whose sum is σ = 60944400. Its totient is φ = 52512768.

The previous prime is 56629711. The next prime is 56629723. The reversal of 56629721 is 12792665.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 978121 + 55651600 = 989^2 + 7460^2 .

It is a de Polignac number, because none of the positive numbers 2^k-56629721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56629723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95201 + ... + 95793.

It is an arithmetic number, because the mean of its divisors is an integer number (3809025).

Almost surely, 2^56629721 is an apocalyptic number.

It is an amenable number.

56629721 is a deficient number, since it is larger than the sum of its proper divisors (4314679).

56629721 is a wasteful number, since it uses less digits than its factorization.

56629721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 748.

The product of its digits is 45360, while the sum is 38.

The square root of 56629721 is about 7525.2721545470. The cubic root of 56629721 is about 384.0149575518.

The spelling of 56629721 in words is "fifty-six million, six hundred twenty-nine thousand, seven hundred twenty-one".