21358804 has 6 divisors (see below), whose sum is σ = 37377914. Its totient is φ = 10679400.

The previous prime is 21358787. The next prime is 21358811. The reversal of 21358804 is 40885312.

It can be written as a sum of positive squares in only one way, i.e., 19342404 + 2016400 = 4398^2 + 1420^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2669847 + ... + 2669854.

Almost surely, 2^21358804 is an apocalyptic number.

It is an amenable number.

21358804 is a deficient number, since it is larger than the sum of its proper divisors (16019110).

21358804 is a wasteful number, since it uses less digits than its factorization.

21358804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5339705 (or 5339703 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 21358804 is about 4621.5586115509. The cubic root of 21358804 is about 277.4548431784.

The spelling of 21358804 in words is "twenty-one million, three hundred fifty-eight thousand, eight hundred four".