18009198 has 48 divisors (see below), whose sum is σ = 40257360. Its totient is φ = 5816448.

The previous prime is 18009197. The next prime is 18009223. The reversal of 18009198 is 89190081.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18009191) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131386 + ... + 131522.

It is an arithmetic number, because the mean of its divisors is an integer number (838695).

Almost surely, 2^18009198 is an apocalyptic number.

18009198 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18009198 is an abundant number, since it is smaller than the sum of its proper divisors (22248162).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18009198 is a wasteful number, since it uses less digits than its factorization.

18009198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 18009198 is about 4243.7245433699. The cubic root of 18009198 is about 262.1187717811.

The spelling of 18009198 in words is "eighteen million, nine thousand, one hundred ninety-eight".