21379504 has 20 divisors (see below), whose sum is σ = 41828176. Its totient is φ = 10585152.

The previous prime is 21379493. The next prime is 21379517. The reversal of 21379504 is 40597312.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4839 + ... + 8134.

Almost surely, 2^21379504 is an apocalyptic number.

It is an amenable number.

21379504 is a deficient number, since it is larger than the sum of its proper divisors (20448672).

21379504 is a wasteful number, since it uses less digits than its factorization.

21379504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13084 (or 13078 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 21379504 is about 4623.7975734238. The cubic root of 21379504 is about 277.5444465236.

The spelling of 21379504 in words is "twenty-one million, three hundred seventy-nine thousand, five hundred four".