18013859 has 4 divisors (see below), whose sum is σ = 18031104. Its totient is φ = 17996616.

The previous prime is 18013841. The next prime is 18013871. The reversal of 18013859 is 95831081.

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

It is a cyclic number.

It is not a de Polignac number, because 18013859 - 2¹² = 18009763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18013819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6947 + ... + 9180.

It is an arithmetic number, because the mean of its divisors is an integer number (4507776).

Almost surely, 2^18013859 is an apocalyptic number.

18013859 is a deficient number, since it is larger than the sum of its proper divisors (17245).

18013859 is a wasteful number, since it uses less digits than its factorization.

18013859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17244.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 18013859 is about 4244.2736716663. The cubic root of 18013859 is about 262.1413830085.

The spelling of 18013859 in words is "eighteen million, thirteen thousand, eight hundred fifty-nine".