18090139 has 4 divisors (see below), whose sum is σ = 18119440. Its totient is φ = 18060840.

The previous prime is 18090097. The next prime is 18090157. The reversal of 18090139 is 93109081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93109081 = 13 ⋅7162237.

It is a cyclic number.

It is not a de Polignac number, because 18090139 - 2²¹ = 15992987 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18090139.

It is not an unprimeable number, because it can be changed into a prime (18090539) 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, 13704 + ... + 14965.

It is an arithmetic number, because the mean of its divisors is an integer number (4529860).

Almost surely, 2^18090139 is an apocalyptic number.

18090139 is a deficient number, since it is larger than the sum of its proper divisors (29301).

18090139 is an equidigital number, since it uses as much as digits as its factorization.

18090139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29300.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 18090139 is about 4253.2504041027. The cubic root of 18090139 is about 262.5108760422.

The spelling of 18090139 in words is "eighteen million, ninety thousand, one hundred thirty-nine".