20797517688 has 16 divisors (see below), whose sum is σ = 51993794280. Its totient is φ = 6932505888.

The previous prime is 20797517683. The next prime is 20797517711. The reversal of 20797517688 is 88671579702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20797517683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 433281595 + ... + 433281642.

Almost surely, 2^20797517688 is an apocalyptic number.

It is an amenable number.

20797517688 is an abundant number, since it is smaller than the sum of its proper divisors (31196276592).

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

20797517688 is a wasteful number, since it uses less digits than its factorization.

20797517688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 866563246 (or 866563242 counting only the distinct ones).

The product of its (nonzero) digits is 11854080, while the sum is 60.

The spelling of 20797517688 in words is "twenty billion, seven hundred ninety-seven million, five hundred seventeen thousand, six hundred eighty-eight".