20556564936 has 32 divisors (see below), whose sum is σ = 51553549440. Its totient is φ = 6830570048.

The previous prime is 20556564923. The next prime is 20556564967. The reversal of 20556564936 is 63946565502.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1343376 + ... + 1358591.

It is an arithmetic number, because the mean of its divisors is an integer number (1611048420).

Almost surely, 2^20556564936 is an apocalyptic number.

It is an amenable number.

20556564936 is an abundant number, since it is smaller than the sum of its proper divisors (30996984504).

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

20556564936 is a wasteful number, since it uses less digits than its factorization.

20556564936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2702293 (or 2702289 counting only the distinct ones).

The product of its (nonzero) digits is 5832000, while the sum is 51.

The spelling of 20556564936 in words is "twenty billion, five hundred fifty-six million, five hundred sixty-four thousand, nine hundred thirty-six".