18136539 has 12 divisors (see below), whose sum is σ = 26249496. Its totient is φ = 12066912.

The previous prime is 18136537. The next prime is 18136561. The reversal of 18136539 is 93563181.

It is a happy number.

It is not a de Polignac number, because 18136539 - 2¹ = 18136537 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (18136537) 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, 3567 + ... + 6999.

It is an arithmetic number, because the mean of its divisors is an integer number (2187458).

Almost surely, 2^18136539 is an apocalyptic number.

18136539 is a deficient number, since it is larger than the sum of its proper divisors (8112957).

18136539 is a wasteful number, since it uses less digits than its factorization.

18136539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4026 (or 4023 counting only the distinct ones).

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

The square root of 18136539 is about 4258.7015626832. The cubic root of 18136539 is about 262.7351253860.

The spelling of 18136539 in words is "eighteen million, one hundred thirty-six thousand, five hundred thirty-nine".