18509249 has 24 divisors (see below), whose sum is σ = 21897120. Its totient is φ = 15586560.

The previous prime is 18509207. The next prime is 18509261. The reversal of 18509249 is 94290581.

It is not a de Polignac number, because 18509249 - 2⁸ = 18508993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18509269) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 190769 + ... + 190865.

It is an arithmetic number, because the mean of its divisors is an integer number (912380).

Almost surely, 2^18509249 is an apocalyptic number.

18509249 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18509249 is a deficient number, since it is larger than the sum of its proper divisors (3387871).

18509249 is a wasteful number, since it uses less digits than its factorization.

18509249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 18509249 is about 4302.2376735834. The cubic root of 18509249 is about 264.5226912969.

The spelling of 18509249 in words is "eighteen million, five hundred nine thousand, two hundred forty-nine".