18138365 has 8 divisors (see below), whose sum is σ = 24875520. Its totient is φ = 12437712.

The previous prime is 18138361. The next prime is 18138397. The reversal of 18138365 is 56383181.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18138365 - 2² = 18138361 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35), and also a Moran number because the ratio is a prime number: 518239 = 18138365 / (1 + 8 + 1 + 3 + 8 + 3 + 6 + 5).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18138361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 259085 + ... + 259154.

It is an arithmetic number, because the mean of its divisors is an integer number (3109440).

Almost surely, 2^18138365 is an apocalyptic number.

It is an amenable number.

18138365 is a deficient number, since it is larger than the sum of its proper divisors (6737155).

18138365 is an equidigital number, since it uses as much as digits as its factorization.

18138365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 518251.

The product of its digits is 17280, while the sum is 35.

The square root of 18138365 is about 4258.9159418800. The cubic root of 18138365 is about 262.7439425449.

The spelling of 18138365 in words is "eighteen million, one hundred thirty-eight thousand, three hundred sixty-five".