19816798888 has 16 divisors (see below), whose sum is σ = 37160424180. Its totient is φ = 9907352448.

The previous prime is 19816798861. The next prime is 19816798891. The reversal of 19816798888 is 88889761891.

It can be written as a sum of positive squares in 2 ways, for example, as 18139241124 + 1677557764 = 134682^2 + 40958^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19816798888.

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, 47295 + ... + 204622.

Almost surely, 2^19816798888 is an apocalyptic number.

It is an amenable number.

19816798888 is a deficient number, since it is larger than the sum of its proper divisors (17343625292).

19816798888 is a wasteful number, since it uses less digits than its factorization.

19816798888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261756 (or 261752 counting only the distinct ones).

The product of its digits is 111476736, while the sum is 73.

The spelling of 19816798888 in words is "nineteen billion, eight hundred sixteen million, seven hundred ninety-eight thousand, eight hundred eighty-eight".