18318643199 has 4 divisors (see below), whose sum is σ = 19396210464. Its totient is φ = 17241075936.

The previous prime is 18318643159. The next prime is 18318643207. The reversal of 18318643199 is 99134681381.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18318643199 - 2³² = 14023675903 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18318643199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18318643159) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 538783607 + ... + 538783640.

It is an arithmetic number, because the mean of its divisors is an integer number (4849052616).

Almost surely, 2^18318643199 is an apocalyptic number.

18318643199 is a deficient number, since it is larger than the sum of its proper divisors (1077567265).

18318643199 is a wasteful number, since it uses less digits than its factorization.

18318643199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1077567264.

The product of its digits is 1119744, while the sum is 53.

The spelling of 18318643199 in words is "eighteen billion, three hundred eighteen million, six hundred forty-three thousand, one hundred ninety-nine".