18398887 has 8 divisors (see below), whose sum is σ = 19894896. Its totient is φ = 16914432.

The previous prime is 18398857. The next prime is 18398899. The reversal of 18398887 is 78889381.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18398887 - 2²³ = 10010279 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 (18398837) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 588 + ... + 6094.

It is an arithmetic number, because the mean of its divisors is an integer number (2486862).

Almost surely, 2^18398887 is an apocalyptic number.

18398887 is a deficient number, since it is larger than the sum of its proper divisors (1496009).

18398887 is a wasteful number, since it uses less digits than its factorization.

18398887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5777.

The product of its digits is 774144, while the sum is 52.

The square root of 18398887 is about 4289.3923812121. The cubic root of 18398887 is about 263.9959011837.

The spelling of 18398887 in words is "eighteen million, three hundred ninety-eight thousand, eight hundred eighty-seven".