18365139 has 12 divisors (see below), whose sum is σ = 28568176. Its totient is φ = 11301552.

The previous prime is 18365131. The next prime is 18365143. The reversal of 18365139 is 93156381.

It is a happy number.

It is not a de Polignac number, because 18365139 - 2³ = 18365131 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18365131) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 78367 + ... + 78600.

Almost surely, 2^18365139 is an apocalyptic number.

18365139 is a deficient number, since it is larger than the sum of its proper divisors (10203037).

18365139 is a wasteful number, since it uses less digits than its factorization.

18365139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156986 (or 156983 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 18365139 is about 4285.4566851154. The cubic root of 18365139 is about 263.8343916583.

The spelling of 18365139 in words is "eighteen million, three hundred sixty-five thousand, one hundred thirty-nine".