20775908988 has 18 divisors (see below), whose sum is σ = 52516881144. Its totient is φ = 6925302984.

The previous prime is 20775908977. The next prime is 20775909001. The reversal of 20775908988 is 88980957702.

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 288554256 + ... + 288554327.

It is an arithmetic number, because the mean of its divisors is an integer number (2917604508).

Almost surely, 2^20775908988 is an apocalyptic number.

It is an amenable number.

20775908988 is an abundant number, since it is smaller than the sum of its proper divisors (31740972156).

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

20775908988 is a wasteful number, since it uses less digits than its factorization.

20775908988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577108593 (or 577108588 counting only the distinct ones).

The product of its (nonzero) digits is 20321280, while the sum is 63.

The spelling of 20775908988 in words is "twenty billion, seven hundred seventy-five million, nine hundred eight thousand, nine hundred eighty-eight".