18672289 has 4 divisors (see below), whose sum is σ = 18882180. Its totient is φ = 18462400.

The previous prime is 18672281. The next prime is 18672319. The reversal of 18672289 is 98227681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10291264 + 8381025 = 3208^2 + 2895^2 .

It is a cyclic number.

It is not a de Polignac number, because 18672289 - 2³ = 18672281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18672281) 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, 104812 + ... + 104989.

It is an arithmetic number, because the mean of its divisors is an integer number (4720545).

Almost surely, 2^18672289 is an apocalyptic number.

It is an amenable number.

18672289 is a deficient number, since it is larger than the sum of its proper divisors (209891).

18672289 is an equidigital number, since it uses as much as digits as its factorization.

18672289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209890.

The product of its digits is 96768, while the sum is 43.

The square root of 18672289 is about 4321.1444086029. The cubic root of 18672289 is about 265.2971106934.

The spelling of 18672289 in words is "eighteen million, six hundred seventy-two thousand, two hundred eighty-nine".