21370804 has 24 divisors (see below), whose sum is σ = 46030208. Its totient is φ = 8454240.

The previous prime is 21370771. The next prime is 21370807. The reversal of 21370804 is 40807312.

It is a super-2 number, since 2×21370804² = 913422527212832, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21370807) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28992 + ... + 29719.

Almost surely, 2^21370804 is an apocalyptic number.

It is an amenable number.

21370804 is an abundant number, since it is smaller than the sum of its proper divisors (24659404).

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

21370804 is a wasteful number, since it uses less digits than its factorization.

21370804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58735 (or 58733 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 21370804 is about 4622.8566925658. The cubic root of 21370804 is about 277.5067941956.

It can be divided in two parts, 213 and 70804, that added together give a palindrome (71017).

The spelling of 21370804 in words is "twenty-one million, three hundred seventy thousand, eight hundred four".