20204656 has 20 divisors (see below), whose sum is σ = 39242032. Its totient is φ = 10077696.

The previous prime is 20204647. The next prime is 20204659. The reversal of 20204656 is 65640202.

It is a self number, because there is not a number n which added to its sum of digits gives 20204656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20204659) 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, 6496 + ... + 9088.

Almost surely, 2^20204656 is an apocalyptic number.

It is an amenable number.

20204656 is a deficient number, since it is larger than the sum of its proper divisors (19037376).

20204656 is a wasteful number, since it uses less digits than its factorization.

20204656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3088 (or 3082 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 20204656 is about 4494.9589542064. The cubic root of 20204656 is about 272.3644911642.

Adding to 20204656 its reverse (65640202), we get a palindrome (85844858).

The spelling of 20204656 in words is "twenty million, two hundred four thousand, six hundred fifty-six".