18344478799 has 4 divisors (see below), whose sum is σ = 18345263440. Its totient is φ = 18343694160.

The previous prime is 18344478767. The next prime is 18344478857. The reversal of 18344478799 is 99787444381.

It is a happy number.

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 18344478799 - 2⁵ = 18344478767 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 18344478799.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18344478199) 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, 356139 + ... + 404380.

It is an arithmetic number, because the mean of its divisors is an integer number (4586315860).

Almost surely, 2^18344478799 is an apocalyptic number.

18344478799 is a deficient number, since it is larger than the sum of its proper divisors (784641).

18344478799 is an equidigital number, since it uses as much as digits as its factorization.

18344478799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784640.

The product of its digits is 48771072, while the sum is 64.

The spelling of 18344478799 in words is "eighteen billion, three hundred forty-four million, four hundred seventy-eight thousand, seven hundred ninety-nine".