18012139 has 8 divisors (see below), whose sum is σ = 18520128. Its totient is φ = 17509440.

The previous prime is 18012131. The next prime is 18012143. The reversal of 18012139 is 93121081.

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

It is a cyclic number.

It is not a de Polignac number, because 18012139 - 2³ = 18012131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18012131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6159 + ... + 8599.

It is an arithmetic number, because the mean of its divisors is an integer number (2315016).

Almost surely, 2^18012139 is an apocalyptic number.

18012139 is a deficient number, since it is larger than the sum of its proper divisors (507989).

18012139 is a wasteful number, since it uses less digits than its factorization.

18012139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2645.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 18012139 is about 4244.0710408757. The cubic root of 18012139 is about 262.1330394783.

The spelling of 18012139 in words is "eighteen million, twelve thousand, one hundred thirty-nine".