19919568464 has 80 divisors (see below), whose sum is σ = 39804773760. Its totient is φ = 9653360640.

The previous prime is 19919568463. The next prime is 19919568469. The reversal of 19919568464 is 46486591991.

It is a junction number, because it is equal to n+sod(n) for n = 19919568397 and 19919568406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19919568463) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26809277 + ... + 26810019.

It is an arithmetic number, because the mean of its divisors is an integer number (497559672).

Almost surely, 2^19919568464 is an apocalyptic number.

It is an amenable number.

19919568464 is a deficient number, since it is larger than the sum of its proper divisors (19885205296).

19919568464 is a wasteful number, since it uses less digits than its factorization.

19919568464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1188 (or 1182 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 62.

The spelling of 19919568464 in words is "nineteen billion, nine hundred nineteen million, five hundred sixty-eight thousand, four hundred sixty-four".