19513854864 has 135 divisors (see below), whose sum is σ = 63566109243. Its totient is φ = 5572034496.

The previous prime is 19513854851. The next prime is 19513854929. The reversal of 19513854864 is 46845831591.

It is a happy number.

The square root of 19513854864 is 139692.

It is a perfect power (a square), and thus also a powerful number.

19513854864 is a `hidden beast` number, since 1 + 9 + 5 + 1 + 38 + 548 + 64 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 19513854864.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 11733297 + ... + 11734959.

Almost surely, 2^19513854864 is an apocalyptic number.

19513854864 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

19513854864 is the 139692-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19513854864

19513854864 is an abundant number, since it is smaller than the sum of its proper divisors (44052254379).

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

19513854864 is an equidigital number, since it uses as much as digits as its factorization.

19513854864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3354 (or 1675 counting only the distinct ones).

The product of its digits is 4147200, while the sum is 54.

The spelling of 19513854864 in words is "nineteen billion, five hundred thirteen million, eight hundred fifty-four thousand, eight hundred sixty-four".