56511021 has 8 divisors (see below), whose sum is σ = 86112064. Its totient is φ = 32292000.

The previous prime is 56511001. The next prime is 56511029. The reversal of 56511021 is 12011565.

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

It is not a de Polignac number, because 56511021 - 2⁵ = 56510989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 2691001 = 56511021 / (5 + 6 + 5 + 1 + 1 + 0 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56511029) 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, 1345480 + ... + 1345521.

It is an arithmetic number, because the mean of its divisors is an integer number (10764008).

Almost surely, 2^56511021 is an apocalyptic number.

It is an amenable number.

56511021 is a deficient number, since it is larger than the sum of its proper divisors (29601043).

56511021 is a wasteful number, since it uses less digits than its factorization.

56511021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2691011.

The product of its (nonzero) digits is 300, while the sum is 21.

The square root of 56511021 is about 7517.3812594547. The cubic root of 56511021 is about 383.7464621403.

Adding to 56511021 its reverse (12011565), we get a palindrome (68522586).

The spelling of 56511021 in words is "fifty-six million, five hundred eleven thousand, twenty-one".