19995796872 has 48 divisors (see below), whose sum is σ = 54171727740. Its totient is φ = 6663241728.

The previous prime is 19995796867. The next prime is 19995796913. The reversal of 19995796872 is 27869759991.

It can be written as a sum of positive squares in 2 ways, for example, as 19542362436 + 453434436 = 139794^2 + 21294^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 19995796872.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 206728 + ... + 287624.

Almost surely, 2^19995796872 is an apocalyptic number.

19995796872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

19995796872 is an abundant number, since it is smaller than the sum of its proper divisors (34175930868).

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

19995796872 is a wasteful number, since it uses less digits than its factorization.

19995796872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84342 (or 84335 counting only the distinct ones).

The product of its digits is 154314720, while the sum is 72.

The spelling of 19995796872 in words is "nineteen billion, nine hundred ninety-five million, seven hundred ninety-six thousand, eight hundred seventy-two".