21552656 has 20 divisors (see below), whose sum is σ = 43574592. Its totient is φ = 10307616.

The previous prime is 21552653. The next prime is 21552659. The reversal of 21552656 is 65625512.

It is an interprime number because it is at equal distance from previous prime (21552653) and next prime (21552659).

It is not an unprimeable number, because it can be changed into a prime (21552653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28916 + ... + 29651.

Almost surely, 2^21552656 is an apocalyptic number.

It is an amenable number.

21552656 is an abundant number, since it is smaller than the sum of its proper divisors (22021936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21552656 is a wasteful number, since it uses less digits than its factorization.

21552656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58598 (or 58592 counting only the distinct ones).

The product of its digits is 18000, while the sum is 32.

The square root of 21552656 is about 4642.4838179578. The cubic root of 21552656 is about 278.2917076726.

The spelling of 21552656 in words is "twenty-one million, five hundred fifty-two thousand, six hundred fifty-six".