21924928 has 28 divisors (see below), whose sum is σ = 45011340. Its totient is φ = 10583552.

The previous prime is 21924923. The next prime is 21924937. The reversal of 21924928 is 82942912.

It can be written as a sum of positive squares in 2 ways, for example, as 10036224 + 11888704 = 3168^2 + 3448^2 .

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21924923) 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, 4051 + ... + 7762.

Almost surely, 2^21924928 is an apocalyptic number.

It is an amenable number.

21924928 is an abundant number, since it is smaller than the sum of its proper divisors (23086412).

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

21924928 is a wasteful number, since it uses less digits than its factorization.

21924928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11854 (or 11844 counting only the distinct ones).

The product of its digits is 20736, while the sum is 37.

The square root of 21924928 is about 4682.4062190288. The cubic root of 21924928 is about 279.8848506107.

The spelling of 21924928 in words is "twenty-one million, nine hundred twenty-four thousand, nine hundred twenty-eight".