18238204559 has 4 divisors (see below), whose sum is σ = 18247151280. Its totient is φ = 18229257840.

The previous prime is 18238204553. The next prime is 18238204561. The reversal of 18238204559 is 95540283281.

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 18238204559 - 2²⁰ = 18237155983 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 (18238204553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4470302 + ... + 4474379.

It is an arithmetic number, because the mean of its divisors is an integer number (4561787820).

Almost surely, 2^18238204559 is an apocalyptic number.

18238204559 is a deficient number, since it is larger than the sum of its proper divisors (8946721).

18238204559 is an equidigital number, since it uses as much as digits as its factorization.

18238204559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8946720.

The product of its (nonzero) digits is 691200, while the sum is 47.

The spelling of 18238204559 in words is "eighteen billion, two hundred thirty-eight million, two hundred four thousand, five hundred fifty-nine".