18000889 has 2 divisors, whose sum is σ = 18000890. Its totient is φ = 18000888.

The previous prime is 18000887. The next prime is 18000893. The reversal of 18000889 is 98800081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10188864 + 7812025 = 3192^2 + 2795^2 .

It is a cyclic number.

It is not a de Polignac number, because 18000889 - 2¹ = 18000887 is a prime.

Together with 18000887, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18000883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9000444 + 9000445.

It is an arithmetic number, because the mean of its divisors is an integer number (9000445).

Almost surely, 2^18000889 is an apocalyptic number.

It is an amenable number.

18000889 is a deficient number, since it is larger than the sum of its proper divisors (1).

18000889 is an equidigital number, since it uses as much as digits as its factorization.

18000889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 34.

The square root of 18000889 is about 4242.7454554804. The cubic root of 18000889 is about 262.0784538667.

The spelling of 18000889 in words is "eighteen million, eight hundred eighty-nine", and thus it is an aban number.