20901888056 has 96 divisors (see below), whose sum is σ = 46170109440. Its totient is φ = 8844437952.

The previous prime is 20901888047. The next prime is 20901888071. The reversal of 20901888056 is 65088810902.

It is a self number, because there is not a number n which added to its sum of digits gives 20901888056.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19662581 + ... + 19663643.

It is an arithmetic number, because the mean of its divisors is an integer number (480938640).

Almost surely, 2^20901888056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20901888056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23085054720).

20901888056 is an abundant number, since it is smaller than the sum of its proper divisors (25268221384).

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

20901888056 is a wasteful number, since it uses less digits than its factorization.

20901888056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1673 (or 1662 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 47.

The spelling of 20901888056 in words is "twenty billion, nine hundred one million, eight hundred eighty-eight thousand, fifty-six".