20856644888 has 32 divisors (see below), whose sum is σ = 43585873200. Its totient is φ = 9298317312.

The previous prime is 20856644873. The next prime is 20856644903. The reversal of 20856644888 is 88844665802.

It is an interprime number because it is at equal distance from previous prime (20856644873) and next prime (20856644903).

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, 4033145 + ... + 4038312.

Almost surely, 2^20856644888 is an apocalyptic number.

It is an amenable number.

20856644888 is an abundant number, since it is smaller than the sum of its proper divisors (22729228312).

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

20856644888 is a wasteful number, since it uses less digits than its factorization.

20856644888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8071499 (or 8071495 counting only the distinct ones).

The product of its (nonzero) digits is 23592960, while the sum is 59.

The spelling of 20856644888 in words is "twenty billion, eight hundred fifty-six million, six hundred forty-four thousand, eight hundred eighty-eight".