18111223384439 has 4 divisors (see below), whose sum is σ = 18735748328760. Its totient is φ = 17486698440120.

The previous prime is 18111223384433. The next prime is 18111223384459. The reversal of 18111223384439 is 93448332211181.

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 18111223384439 - 2²⁴ = 18111206607223 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 (18111223384433) 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, 312262472117 + ... + 312262472174.

It is an arithmetic number, because the mean of its divisors is an integer number (4683937082190).

Almost surely, 2^{18111223384439} is an apocalyptic number.

18111223384439 is a deficient number, since it is larger than the sum of its proper divisors (624524944321).

18111223384439 is an equidigital number, since it uses as much as digits as its factorization.

18111223384439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624524944320.

The product of its digits is 995328, while the sum is 50.

The spelling of 18111223384439 in words is "eighteen trillion, one hundred eleven billion, two hundred twenty-three million, three hundred eighty-four thousand, four hundred thirty-nine".