21938872 has 16 divisors (see below), whose sum is σ = 42924240. Its totient is φ = 10492416.

The previous prime is 21938867. The next prime is 21938881. The reversal of 21938872 is 27883912.

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, 59433 + ... + 59800.

It is an arithmetic number, because the mean of its divisors is an integer number (2682765).

Almost surely, 2^21938872 is an apocalyptic number.

It is an amenable number.

21938872 is a deficient number, since it is larger than the sum of its proper divisors (20985368).

21938872 is a wasteful number, since it uses less digits than its factorization.

21938872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119262 (or 119258 counting only the distinct ones).

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

The square root of 21938872 is about 4683.8949603935. The cubic root of 21938872 is about 279.9441725431.

The spelling of 21938872 in words is "twenty-one million, nine hundred thirty-eight thousand, eight hundred seventy-two".