19664221298 has 18 divisors (see below), whose sum is σ = 29694276999. Its totient is φ = 9766567872.

The previous prime is 19664221259. The next prime is 19664221327. The reversal of 19664221298 is 89212246691.

It can be written as a sum of positive squares in 5 ways, for example, as 11327983489 + 8336237809 = 106433^2 + 91303^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=99157.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 45413690 + ... + 45414122.

Almost surely, 2^19664221298 is an apocalyptic number.

19664221298 is a deficient number, since it is larger than the sum of its proper divisors (10030055701).

19664221298 is an frugal number, since it uses more digits than its factorization.

19664221298 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1326 (or 664 counting only the distinct ones).

The product of its digits is 746496, while the sum is 50.

Multiplying 19664221298 by its sum of digits (50), we get a square (983211064900 = 991570²).

The spelling of 19664221298 in words is "nineteen billion, six hundred sixty-four million, two hundred twenty-one thousand, two hundred ninety-eight".