21495564 has 24 divisors (see below), whose sum is σ = 55729520. Its totient is φ = 7165152.

The previous prime is 21495541. The next prime is 21495569. The reversal of 21495564 is 46559412.

21495564 is a `hidden beast` number, since 2 + 1 + 4 + 95 + 564 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21495569) 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, 99409 + ... + 99624.

Almost surely, 2^21495564 is an apocalyptic number.

It is an amenable number.

21495564 is an abundant number, since it is smaller than the sum of its proper divisors (34233956).

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

21495564 is a wasteful number, since it uses less digits than its factorization.

21495564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199046 (or 199038 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 21495564 is about 4636.3308768896. The cubic root of 21495564 is about 278.0457630441.

The spelling of 21495564 in words is "twenty-one million, four hundred ninety-five thousand, five hundred sixty-four".