18399534 has 8 divisors (see below), whose sum is σ = 36799080. Its totient is φ = 6133176.

The previous prime is 18399509. The next prime is 18399541. The reversal of 18399534 is 43599381.

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

18399534 is an admirable number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1533289 + ... + 1533300.

It is an arithmetic number, because the mean of its divisors is an integer number (4599885).

Almost surely, 2^18399534 is an apocalyptic number.

18399534 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18399534 is a wasteful number, since it uses less digits than its factorization.

18399534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3066594.

The product of its digits is 116640, while the sum is 42.

The square root of 18399534 is about 4289.4677991564. The cubic root of 18399534 is about 263.9989956344.

The spelling of 18399534 in words is "eighteen million, three hundred ninety-nine thousand, five hundred thirty-four".