21074872 has 32 divisors (see below), whose sum is σ = 48636000. Its totient is φ = 8337024.

The previous prime is 21074843. The next prime is 21074897. The reversal of 21074872 is 27847012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13747 + ... + 15202.

It is an arithmetic number, because the mean of its divisors is an integer number (1519875).

Almost surely, 2^21074872 is an apocalyptic number.

It is an amenable number.

21074872 is an abundant number, since it is smaller than the sum of its proper divisors (27561128).

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

21074872 is a wasteful number, since it uses less digits than its factorization.

21074872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28975 (or 28971 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 21074872 is about 4590.7376313617. The cubic root of 21074872 is about 276.2199115486.

The spelling of 21074872 in words is "twenty-one million, seventy-four thousand, eight hundred seventy-two".