18609 has 4 divisors (see below), whose sum is σ = 24816. Its totient is φ = 12404.

The previous prime is 18593. The next prime is 18617. The reversal of 18609 is 90681.

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.

It is a cyclic number.

It is not a de Polignac number, because 18609 - 2⁴ = 18593 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (18679) 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, 3099 + ... + 3104.

It is an arithmetic number, because the mean of its divisors is an integer number (6204).

2¹⁸⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

18609 is a deficient number, since it is larger than the sum of its proper divisors (6207).

18609 is an equidigital number, since it uses as much as digits as its factorization.

18609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6206.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 18609 is about 136.4148085803. The cubic root of 18609 is about 26.4997033312.

The spelling of 18609 in words is "eighteen thousand, six hundred nine".