21912524 has 12 divisors (see below), whose sum is σ = 40602744. Its totient is φ = 10311744.

The previous prime is 21912521. The next prime is 21912563. The reversal of 21912524 is 42521912.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21912493 and 21912502.

It is not an unprimeable number, because it can be changed into a prime (21912521) 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, 161054 + ... + 161189.

It is an arithmetic number, because the mean of its divisors is an integer number (3383562).

Almost surely, 2^21912524 is an apocalyptic number.

It is an amenable number.

21912524 is a deficient number, since it is larger than the sum of its proper divisors (18690220).

21912524 is a wasteful number, since it uses less digits than its factorization.

21912524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322264 (or 322262 counting only the distinct ones).

The product of its digits is 1440, while the sum is 26.

The square root of 21912524 is about 4681.0814989701. The cubic root of 21912524 is about 279.8320591551.

The spelling of 21912524 in words is "twenty-one million, nine hundred twelve thousand, five hundred twenty-four".