18398389 has 4 divisors (see below), whose sum is σ = 18631360. Its totient is φ = 18165420.

The previous prime is 18398353. The next prime is 18398417. The reversal of 18398389 is 98389381.

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 18398389 - 2⁹ = 18397877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18398309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116367 + ... + 116524.

It is an arithmetic number, because the mean of its divisors is an integer number (4657840).

Almost surely, 2^18398389 is an apocalyptic number.

It is an amenable number.

18398389 is a deficient number, since it is larger than the sum of its proper divisors (232971).

18398389 is an equidigital number, since it uses as much as digits as its factorization.

18398389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232970.

The product of its digits is 373248, while the sum is 49.

The square root of 18398389 is about 4289.3343306392. The cubic root of 18398389 is about 263.9935193160.

The spelling of 18398389 in words is "eighteen million, three hundred ninety-eight thousand, three hundred eighty-nine".