18616138 has 4 divisors (see below), whose sum is σ = 27924210. Its totient is φ = 9308068.

The previous prime is 18616133. The next prime is 18616187. The reversal of 18616138 is 83161681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18003049 + 613089 = 4243^2 + 783^2 .

It is not an unprimeable number, because it can be changed into a prime (18616133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4654033 + ... + 4654036.

Almost surely, 2^18616138 is an apocalyptic number.

18616138 is a deficient number, since it is larger than the sum of its proper divisors (9308072).

18616138 is an equidigital number, since it uses as much as digits as its factorization.

18616138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9308071.

The product of its digits is 6912, while the sum is 34.

The square root of 18616138 is about 4314.6422794943. The cubic root of 18616138 is about 265.0309113105.

The spelling of 18616138 in words is "eighteen million, six hundred sixteen thousand, one hundred thirty-eight".