21838972 has 24 divisors (see below), whose sum is σ = 40093200. Its totient is φ = 10394496.

The previous prime is 21838967. The next prime is 21839003. The reversal of 21838972 is 27983812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7179 + ... + 9757.

It is an arithmetic number, because the mean of its divisors is an integer number (1670550).

Almost surely, 2^21838972 is an apocalyptic number.

It is an amenable number.

21838972 is a deficient number, since it is larger than the sum of its proper divisors (18254228).

21838972 is a wasteful number, since it uses less digits than its factorization.

21838972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2685 (or 2683 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The square root of 21838972 is about 4673.2185910783. The cubic root of 21838972 is about 279.5186116256.

The spelling of 21838972 in words is "twenty-one million, eight hundred thirty-eight thousand, nine hundred seventy-two".