18000085 has 4 divisors (see below), whose sum is σ = 21600108. Its totient is φ = 14400064.

The previous prime is 18000067. The next prime is 18000089. The reversal of 18000085 is 58000081.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5340721 + 12659364 = 2311^2 + 3558^2 .

It is a cyclic number.

It is not a de Polignac number, because 18000085 - 2⁹ = 17999573 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18000089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1800004 + ... + 1800013.

It is an arithmetic number, because the mean of its divisors is an integer number (5400027).

Almost surely, 2^18000085 is an apocalyptic number.

It is an amenable number.

18000085 is a deficient number, since it is larger than the sum of its proper divisors (3600023).

18000085 is an equidigital number, since it uses as much as digits as its factorization.

18000085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3600022.

The product of its (nonzero) digits is 320, while the sum is 22.

The square root of 18000085 is about 4242.6507044535. The cubic root of 18000085 is about 262.0745519443.

The spelling of 18000085 in words is "eighteen million, eighty-five", and thus it is an aban number and an uban number.