21938368 has 28 divisors (see below), whose sum is σ = 43698160. Its totient is φ = 10927872.

The previous prime is 21938353. The next prime is 21938377. The reversal of 21938368 is 86383912.

It is a self number, because there is not a number n which added to its sum of digits gives 21938368.

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, 23413 + ... + 24331.

Almost surely, 2^21938368 is an apocalyptic number.

It is an amenable number.

21938368 is a deficient number, since it is larger than the sum of its proper divisors (21759792).

21938368 is an equidigital number, since it uses as much as digits as its factorization.

21938368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1304 (or 1294 counting only the distinct ones).

The product of its digits is 62208, while the sum is 40.

The square root of 21938368 is about 4683.8411587072. The cubic root of 21938368 is about 279.9420288148.

The spelling of 21938368 in words is "twenty-one million, nine hundred thirty-eight thousand, three hundred sixty-eight".