56221631 has 12 divisors (see below), whose sum is σ = 59148864. Its totient is φ = 53383200.

The previous prime is 56221621. The next prime is 56221639. The reversal of 56221631 is 13612265.

It is not a de Polignac number, because 56221631 - 2¹⁰ = 56220607 is a prime.

It is a super-2 number, since 2×56221631² = 6321743584600322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 56221631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56221639) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 107651 + ... + 108171.

It is an arithmetic number, because the mean of its divisors is an integer number (4929072).

Almost surely, 2^56221631 is an apocalyptic number.

56221631 is a deficient number, since it is larger than the sum of its proper divisors (2927233).

56221631 is an equidigital number, since it uses as much as digits as its factorization.

56221631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670 (or 611 counting only the distinct ones).

The product of its digits is 2160, while the sum is 26.

The square root of 56221631 is about 7498.1084948139. The cubic root of 56221631 is about 383.0902922324.

Adding to 56221631 its reverse (13612265), we get a palindrome (69833896).

The spelling of 56221631 in words is "fifty-six million, two hundred twenty-one thousand, six hundred thirty-one".