20718868128 has 96 divisors (see below), whose sum is σ = 62180576640. Its totient is φ = 5917393920.

The previous prime is 20718868091. The next prime is 20718868139. The reversal of 20718868128 is 82186881702.

It is a tau number, because it is divible by the number of its divisors (96).

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, 2563678 + ... + 2571746.

It is an arithmetic number, because the mean of its divisors is an integer number (647714340).

Almost surely, 2^20718868128 is an apocalyptic number.

20718868128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20718868128 is an abundant number, since it is smaller than the sum of its proper divisors (41461708512).

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

20718868128 is a wasteful number, since it uses less digits than its factorization.

20718868128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11910 (or 11902 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 51.

The spelling of 20718868128 in words is "twenty billion, seven hundred eighteen million, eight hundred sixty-eight thousand, one hundred twenty-eight".