20204636856 has 32 divisors (see below), whose sum is σ = 52707749760. Its totient is φ = 6442057952.

The previous prime is 20204636819. The next prime is 20204636873. The reversal of 20204636856 is 65863640202.

It is a happy number.

It is a congruent number.

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, 18300750 + ... + 18301853.

It is an arithmetic number, because the mean of its divisors is an integer number (1647117180).

Almost surely, 2^20204636856 is an apocalyptic number.

It is an amenable number.

20204636856 is an abundant number, since it is smaller than the sum of its proper divisors (32503112904).

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

20204636856 is a wasteful number, since it uses less digits than its factorization.

20204636856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36602635 (or 36602631 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 20204636856 in words is "twenty billion, two hundred four million, six hundred thirty-six thousand, eight hundred fifty-six".