18115138 has 8 divisors (see below), whose sum is σ = 27453132. Its totient is φ = 8964096.

The previous prime is 18115133. The next prime is 18115147. The reversal of 18115138 is 83151181.

It can be written as a sum of positive squares in 2 ways, for example, as 16867449 + 1247689 = 4107^2 + 1117^2 .

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

It is not an unprimeable number, because it can be changed into a prime (18115133) 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, 46495 + ... + 46882.

Almost surely, 2^18115138 is an apocalyptic number.

18115138 is a deficient number, since it is larger than the sum of its proper divisors (9337994).

18115138 is an equidigital number, since it uses as much as digits as its factorization.

18115138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93476.

The product of its digits is 960, while the sum is 28.

The square root of 18115138 is about 4256.1882007261. The cubic root of 18115138 is about 262.6317427893.

The spelling of 18115138 in words is "eighteen million, one hundred fifteen thousand, one hundred thirty-eight".