21632056 has 32 divisors (see below), whose sum is σ = 41711760. Its totient is φ = 10513152.

The previous prime is 21631997. The next prime is 21632059. The reversal of 21632056 is 65023612.

It is a self number, because there is not a number n which added to its sum of digits gives 21632056.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21632059) 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, 68956 + ... + 69268.

Almost surely, 2^21632056 is an apocalyptic number.

It is an amenable number.

21632056 is a deficient number, since it is larger than the sum of its proper divisors (20079704).

21632056 is a wasteful number, since it uses less digits than its factorization.

21632056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 535 (or 531 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 21632056 is about 4651.0274133787. The cubic root of 21632056 is about 278.6330311527.

Adding to 21632056 its reverse (65023612), we get a palindrome (86655668).

The spelling of 21632056 in words is "twenty-one million, six hundred thirty-two thousand, fifty-six".