20021804 has 24 divisors (see below), whose sum is σ = 38535168. Its totient is φ = 9026640.

The previous prime is 20021759. The next prime is 20021821. The reversal of 20021804 is 40812002.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3797 + ... + 7379.

It is an arithmetic number, because the mean of its divisors is an integer number (1605632).

Almost surely, 2^20021804 is an apocalyptic number.

It is an amenable number.

20021804 is a deficient number, since it is larger than the sum of its proper divisors (18513364).

20021804 is a wasteful number, since it uses less digits than its factorization.

20021804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3725 (or 3723 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 20021804 is about 4474.5730522587. The cubic root of 20021804 is about 271.5403677709.

Adding to 20021804 its reverse (40812002), we get a palindrome (60833806).

The spelling of 20021804 in words is "twenty million, twenty-one thousand, eight hundred four".