21912368 has 20 divisors (see below), whose sum is σ = 43492008. Its totient is φ = 10688640.

The previous prime is 21912367. The next prime is 21912383. The reversal of 21912368 is 86321912.

It is not an unprimeable number, because it can be changed into a prime (21912367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16046 + ... + 17357.

Almost surely, 2^21912368 is an apocalyptic number.

It is an amenable number.

21912368 is a deficient number, since it is larger than the sum of its proper divisors (21579640).

21912368 is a wasteful number, since it uses less digits than its factorization.

21912368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33452 (or 33446 counting only the distinct ones).

The product of its digits is 5184, while the sum is 32.

The square root of 21912368 is about 4681.0648361244. The cubic root of 21912368 is about 279.8313950918.

The spelling of 21912368 in words is "twenty-one million, nine hundred twelve thousand, three hundred sixty-eight".