18219639799 has 4 divisors (see below), whose sum is σ = 18274684360. Its totient is φ = 18164595240.

The previous prime is 18219639793. The next prime is 18219639829. The reversal of 18219639799 is 99793691281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99793691281 = 337 ⋅296123713.

It is a cyclic number.

It is not a de Polignac number, because 18219639799 - 2³ = 18219639791 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 18219639799.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18219639791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27521784 + ... + 27522445.

It is an arithmetic number, because the mean of its divisors is an integer number (4568671090).

Almost surely, 2^18219639799 is an apocalyptic number.

18219639799 is a deficient number, since it is larger than the sum of its proper divisors (55044561).

18219639799 is an equidigital number, since it uses as much as digits as its factorization.

18219639799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55044560.

The product of its digits is 13226976, while the sum is 64.

The spelling of 18219639799 in words is "eighteen billion, two hundred nineteen million, six hundred thirty-nine thousand, seven hundred ninety-nine".