56520021 has 8 divisors (see below), whose sum is σ = 75866400. Its totient is φ = 37426832.

The previous prime is 56519989. The next prime is 56520029. The reversal of 56520021 is 12002565.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 56520021 - 2⁵ = 56519989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 56520021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56520029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62775 + ... + 63668.

It is an arithmetic number, because the mean of its divisors is an integer number (9483300).

Almost surely, 2^56520021 is an apocalyptic number.

It is an amenable number.

56520021 is a deficient number, since it is larger than the sum of its proper divisors (19346379).

56520021 is a wasteful number, since it uses less digits than its factorization.

56520021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126595.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 56520021 is about 7517.9798483369. The cubic root of 56520021 is about 383.7668330034.

Adding to 56520021 its reverse (12002565), we get a palindrome (68522586).

The spelling of 56520021 in words is "fifty-six million, five hundred twenty thousand, twenty-one".