18198189 has 10 divisors (see below), whose sum is σ = 27185070. Its totient is φ = 12132072.

The previous prime is 18198179. The next prime is 18198199. The reversal of 18198189 is 98189181.

It is an interprime number because it is at equal distance from previous prime (18198179) and next prime (18198199).

It can be written as a sum of positive squares in only one way, i.e., 12638025 + 5560164 = 3555^2 + 2358^2 .

It is not a de Polignac number, because 18198189 - 2¹¹ = 18196141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18198139) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 112254 + ... + 112415.

It is an arithmetic number, because the mean of its divisors is an integer number (2718507).

Almost surely, 2^18198189 is an apocalyptic number.

It is an amenable number.

18198189 is a deficient number, since it is larger than the sum of its proper divisors (8986881).

18198189 is an equidigital number, since it uses as much as digits as its factorization.

18198189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224681 (or 224672 counting only the distinct ones).

The product of its digits is 41472, while the sum is 45.

The square root of 18198189 is about 4265.9335437862. The cubic root of 18198189 is about 263.0324864572.

The spelling of 18198189 in words is "eighteen million, one hundred ninety-eight thousand, one hundred eighty-nine".