19997816692 has 72 divisors (see below), whose sum is σ = 43492596000. Its totient is φ = 7998129216.

The previous prime is 19997816689. The next prime is 19997816717. The reversal of 19997816692 is 29661879991.

It is a Harshad number since it is a multiple of its sum of digits (67).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 209434 + ... + 289582.

Almost surely, 2^19997816692 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 19997816692, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21746298000).

19997816692 is an abundant number, since it is smaller than the sum of its proper divisors (23494779308).

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

19997816692 is a wasteful number, since it uses less digits than its factorization.

19997816692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80253 (or 80244 counting only the distinct ones).

The product of its digits is 26453952, while the sum is 67.

The spelling of 19997816692 in words is "nineteen billion, nine hundred ninety-seven million, eight hundred sixteen thousand, six hundred ninety-two".