21566052 has 36 divisors (see below), whose sum is σ = 55211520. Its totient is φ = 7096752.

The previous prime is 21566033. The next prime is 21566059. The reversal of 21566052 is 25066512.

21566052 is a `hidden beast` number, since 2 + 1 + 56 + 605 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (21566059) 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, 948 + ... + 6635.

Almost surely, 2^21566052 is an apocalyptic number.

It is an amenable number.

21566052 is an abundant number, since it is smaller than the sum of its proper divisors (33645468).

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

21566052 is a wasteful number, since it uses less digits than its factorization.

21566052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7672 (or 7667 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 21566052 is about 4643.9263560052. The cubic root of 21566052 is about 278.3493529052.

The spelling of 21566052 in words is "twenty-one million, five hundred sixty-six thousand, fifty-two".