20021668556 has 48 divisors (see below), whose sum is σ = 38211747840. Its totient is φ = 9154743360.

The previous prime is 20021668547. The next prime is 20021668561. The reversal of 20021668556 is 65586612002.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109781 + ... + 228243.

It is an arithmetic number, because the mean of its divisors is an integer number (796078080).

Almost surely, 2^20021668556 is an apocalyptic number.

It is an amenable number.

20021668556 is a deficient number, since it is larger than the sum of its proper divisors (18190079284).

20021668556 is a wasteful number, since it uses less digits than its factorization.

20021668556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118574 (or 118572 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 41.

The spelling of 20021668556 in words is "twenty billion, twenty-one million, six hundred sixty-eight thousand, five hundred fifty-six".