18616189 has 4 divisors (see below), whose sum is σ = 18658656. Its totient is φ = 18573724.

The previous prime is 18616187. The next prime is 18616237. The reversal of 18616189 is 98161681.

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, and also an emirpimes, since its reverse is a distinct semiprime: 98161681 = 3307 ⋅29683.

It is a cyclic number.

It is not a de Polignac number, because 18616189 - 2¹ = 18616187 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 (18616187) 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, 20569 + ... + 21454.

It is an arithmetic number, because the mean of its divisors is an integer number (4664664).

Almost surely, 2^18616189 is an apocalyptic number.

It is an amenable number.

18616189 is a deficient number, since it is larger than the sum of its proper divisors (42467).

18616189 is an equidigital number, since it uses as much as digits as its factorization.

18616189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42466.

The product of its digits is 20736, while the sum is 40.

The square root of 18616189 is about 4314.6481895978. The cubic root of 18616189 is about 265.0311533329.

The spelling of 18616189 in words is "eighteen million, six hundred sixteen thousand, one hundred eighty-nine".