18368989 has 4 divisors (see below), whose sum is σ = 18501280. Its totient is φ = 18236700.

The previous prime is 18368981. The next prime is 18369017. The reversal of 18368989 is 98986381.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18368989 - 2³ = 18368981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18368981) 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, 65937 + ... + 66214.

It is an arithmetic number, because the mean of its divisors is an integer number (4625320).

Almost surely, 2^18368989 is an apocalyptic number.

It is an amenable number.

18368989 is a deficient number, since it is larger than the sum of its proper divisors (132291).

18368989 is a wasteful number, since it uses less digits than its factorization.

18368989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132290.

The product of its digits is 746496, while the sum is 52.

The square root of 18368989 is about 4285.9058552423. The cubic root of 18368989 is about 263.8528267930.

The spelling of 18368989 in words is "eighteen million, three hundred sixty-eight thousand, nine hundred eighty-nine".