21534572 has 12 divisors (see below), whose sum is σ = 38562216. Its totient is φ = 10516800.

The previous prime is 21534551. The next prime is 21534577. The reversal of 21534572 is 27543512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21534577) 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, 62429 + ... + 62772.

It is an arithmetic number, because the mean of its divisors is an integer number (3213518).

Almost surely, 2^21534572 is an apocalyptic number.

It is an amenable number.

21534572 is a deficient number, since it is larger than the sum of its proper divisors (17027644).

21534572 is a wasteful number, since it uses less digits than its factorization.

21534572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125248 (or 125246 counting only the distinct ones).

The product of its digits is 8400, while the sum is 29.

The square root of 21534572 is about 4640.5357449329. The cubic root of 21534572 is about 278.2138512906.

The spelling of 21534572 in words is "twenty-one million, five hundred thirty-four thousand, five hundred seventy-two".