21965524 has 18 divisors (see below), whose sum is σ = 44715930. Its totient is φ = 9413712.

The previous prime is 21965521. The next prime is 21965527. The reversal of 21965524 is 42556912.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21965521) and next prime (21965527).

It can be written as a sum of positive squares in only one way, i.e., 18232900 + 3732624 = 4270^2 + 1932^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21965524.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21965521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55839 + ... + 56230.

Almost surely, 2^21965524 is an apocalyptic number.

It is an amenable number.

21965524 is an abundant number, since it is smaller than the sum of its proper divisors (22750406).

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

21965524 is a wasteful number, since it uses less digits than its factorization.

21965524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112087 (or 112078 counting only the distinct ones).

The product of its digits is 21600, while the sum is 34.

The square root of 21965524 is about 4686.7391649205. The cubic root of 21965524 is about 280.0574881960.

The spelling of 21965524 in words is "twenty-one million, nine hundred sixty-five thousand, five hundred twenty-four".