21920204 has 12 divisors (see below), whose sum is σ = 38441928. Its totient is φ = 10936800.

The previous prime is 21920203. The next prime is 21920251. The reversal of 21920204 is 40202912.

It is not an unprimeable number, because it can be changed into a prime (21920203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3617 + ... + 7544.

It is an arithmetic number, because the mean of its divisors is an integer number (3203494).

Almost surely, 2^21920204 is an apocalyptic number.

It is an amenable number.

21920204 is a deficient number, since it is larger than the sum of its proper divisors (16521724).

21920204 is a wasteful number, since it uses less digits than its factorization.

21920204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11656 (or 11654 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 21920204 is about 4681.9017503574. The cubic root of 21920204 is about 279.8647476028.

The spelling of 21920204 in words is "twenty-one million, nine hundred twenty thousand, two hundred four".