18659559799 has 4 divisors (see below), whose sum is σ = 19163872264. Its totient is φ = 18155247336.

The previous prime is 18659559781. The next prime is 18659559833. The reversal of 18659559799 is 99795595681.

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 18659559799 - 2⁷ = 18659559671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18659559739) 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, 252156177 + ... + 252156250.

It is an arithmetic number, because the mean of its divisors is an integer number (4790968066).

Almost surely, 2^18659559799 is an apocalyptic number.

18659559799 is a deficient number, since it is larger than the sum of its proper divisors (504312465).

18659559799 is an equidigital number, since it uses as much as digits as its factorization.

18659559799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504312464.

The product of its digits is 275562000, while the sum is 73.

The spelling of 18659559799 in words is "eighteen billion, six hundred fifty-nine million, five hundred fifty-nine thousand, seven hundred ninety-nine".