20516871888 has 80 divisors (see below), whose sum is σ = 58940691840. Its totient is φ = 6833189376.

The previous prime is 20516871853. The next prime is 20516871901. The reversal of 20516871888 is 88817861502.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

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, 508920 + ... + 547752.

It is an arithmetic number, because the mean of its divisors is an integer number (736758648).

Almost surely, 2^20516871888 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 20516871888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29470345920).

20516871888 is an abundant number, since it is smaller than the sum of its proper divisors (38423819952).

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

20516871888 is a wasteful number, since it uses less digits than its factorization.

20516871888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40073 (or 40061 counting only the distinct ones).

The product of its (nonzero) digits is 1720320, while the sum is 54.

The spelling of 20516871888 in words is "twenty billion, five hundred sixteen million, eight hundred seventy-one thousand, eight hundred eighty-eight".