18345689 has 4 divisors (see below), whose sum is σ = 18646500. Its totient is φ = 18044880.

The previous prime is 18345683. The next prime is 18345709. The reversal of 18345689 is 98654381.

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 537289 + 17808400 = 733^2 + 4220^2 .

It is a cyclic number.

It is not a de Polignac number, because 18345689 - 2²⁰ = 17297113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18345683) 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, 150314 + ... + 150435.

It is an arithmetic number, because the mean of its divisors is an integer number (4661625).

Almost surely, 2^18345689 is an apocalyptic number.

It is an amenable number.

18345689 is a deficient number, since it is larger than the sum of its proper divisors (300811).

18345689 is an equidigital number, since it uses as much as digits as its factorization.

18345689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300810.

The product of its digits is 207360, while the sum is 44.

The square root of 18345689 is about 4283.1867808911. The cubic root of 18345689 is about 263.7412189076.

The spelling of 18345689 in words is "eighteen million, three hundred forty-five thousand, six hundred eighty-nine".