18000065 has 4 divisors (see below), whose sum is σ = 21600084. Its totient is φ = 14400048.

The previous prime is 18000041. The next prime is 18000067. The reversal of 18000065 is 56000081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56000081 = 911 ⋅61471.

It can be written as a sum of positive squares in 2 ways, for example, as 3794704 + 14205361 = 1948^2 + 3769^2 .

It is a cyclic number.

It is not a de Polignac number, because 18000065 - 2¹² = 17995969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18000067) 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, 1800002 + ... + 1800011.

It is an arithmetic number, because the mean of its divisors is an integer number (5400021).

Almost surely, 2^18000065 is an apocalyptic number.

It is an amenable number.

18000065 is a deficient number, since it is larger than the sum of its proper divisors (3600019).

18000065 is an equidigital number, since it uses as much as digits as its factorization.

18000065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3600018.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 18000065 is about 4242.6483474358. The cubic root of 18000065 is about 262.0744548801.

The spelling of 18000065 in words is "eighteen million, sixty-five", and thus it is an aban number and an uban number.