21875164 has 12 divisors (see below), whose sum is σ = 39601800. Its totient is φ = 10560368.

The previous prime is 21875159. The next prime is 21875173. The reversal of 21875164 is 46157812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94174 + ... + 94405.

It is an arithmetic number, because the mean of its divisors is an integer number (3300150).

Almost surely, 2^21875164 is an apocalyptic number.

It is an amenable number.

21875164 is a deficient number, since it is larger than the sum of its proper divisors (17726636).

21875164 is a wasteful number, since it uses less digits than its factorization.

21875164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188612 (or 188610 counting only the distinct ones).

The product of its digits is 13440, while the sum is 34.

The square root of 21875164 is about 4677.0892657720. The cubic root of 21875164 is about 279.6729344328.

The spelling of 21875164 in words is "twenty-one million, eight hundred seventy-five thousand, one hundred sixty-four".