21379264 has 28 divisors (see below), whose sum is σ = 43891200. Its totient is φ = 10320128.

The previous prime is 21379249. The next prime is 21379271. The reversal of 21379264 is 46297312.

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, 3904 + ... + 7615.

Almost surely, 2^21379264 is an apocalyptic number.

It is an amenable number.

21379264 is an abundant number, since it is smaller than the sum of its proper divisors (22511936).

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

21379264 is a wasteful number, since it uses less digits than its factorization.

21379264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11560 (or 11550 counting only the distinct ones).

The product of its digits is 18144, while the sum is 34.

The square root of 21379264 is about 4623.7716206578. The cubic root of 21379264 is about 277.5434079757.

The spelling of 21379264 in words is "twenty-one million, three hundred seventy-nine thousand, two hundred sixty-four".