20688808688 has 20 divisors (see below), whose sum is σ = 40091038920. Its totient is φ = 10342734144.

The previous prime is 20688808661. The next prime is 20688808697. The reversal of 20688808688 is 88680888602.

It is a self number, because there is not a number n which added to its sum of digits gives 20688808688.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1031 + ... + 203417.

It is an arithmetic number, because the mean of its divisors is an integer number (2004551946).

Almost surely, 2^20688808688 is an apocalyptic number.

It is an amenable number.

20688808688 is a deficient number, since it is larger than the sum of its proper divisors (19402230232).

20688808688 is a wasteful number, since it uses less digits than its factorization.

20688808688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208784 (or 208778 counting only the distinct ones).

The product of its (nonzero) digits is 18874368, while the sum is 62.

The spelling of 20688808688 in words is "twenty billion, six hundred eighty-eight million, eight hundred eight thousand, six hundred eighty-eight".