23221904 has 20 divisors (see below), whose sum is σ = 46949376. Its totient is φ = 11105952.

The previous prime is 23221853. The next prime is 23221909. The reversal of 23221904 is 40912232.

23221904 = T₁₅₅ + T₁₅₆ + ... + T₅₂₂.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a self number, because there is not a number n which added to its sum of digits gives 23221904.

It is not an unprimeable number, because it can be changed into a prime (23221909) 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, 31184 + ... + 31919.

Almost surely, 2^23221904 is an apocalyptic number.

It is an amenable number.

23221904 is an abundant number, since it is smaller than the sum of its proper divisors (23727472).

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

23221904 is a wasteful number, since it uses less digits than its factorization.

23221904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63134 (or 63128 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 23221904 is about 4818.9110803168. The cubic root of 23221904 is about 285.2983599568.

The spelling of 23221904 in words is "twenty-three million, two hundred twenty-one thousand, nine hundred four".