21368804 has 6 divisors (see below), whose sum is σ = 37395414. Its totient is φ = 10684400.

The previous prime is 21368803. The next prime is 21368821. The reversal of 21368804 is 40886312.

It can be written as a sum of positive squares in only one way, i.e., 19272100 + 2096704 = 4390^2 + 1448^2 .

It is not an unprimeable number, because it can be changed into a prime (21368801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2671097 + ... + 2671104.

It is an arithmetic number, because the mean of its divisors is an integer number (6232569).

Almost surely, 2^21368804 is an apocalyptic number.

It is an amenable number.

21368804 is a deficient number, since it is larger than the sum of its proper divisors (16026610).

21368804 is a wasteful number, since it uses less digits than its factorization.

21368804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5342205 (or 5342203 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 21368804 is about 4622.6403710434. The cubic root of 21368804 is about 277.4981370435.

The spelling of 21368804 in words is "twenty-one million, three hundred sixty-eight thousand, eight hundred four".