18005994 has 12 divisors (see below), whose sum is σ = 39013026. Its totient is φ = 6001992.

The previous prime is 18005993. The next prime is 18006017. The reversal of 18005994 is 49950081.

It can be written as a sum of positive squares in only one way, i.e., 15563025 + 2442969 = 3945^2 + 1563^2 .

18005994 is a modest number, since divided by 5994 gives 18 as remainder.

It is not an unprimeable number, because it can be changed into a prime (18005993) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 500149 + ... + 500184.

Almost surely, 2^18005994 is an apocalyptic number.

18005994 is an abundant number, since it is smaller than the sum of its proper divisors (21007032).

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

18005994 is a wasteful number, since it uses less digits than its factorization.

18005994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000341 (or 1000338 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 18005994 is about 4243.3470279957. The cubic root of 18005994 is about 262.1032264219.

The spelling of 18005994 in words is "eighteen million, five thousand, nine hundred ninety-four".