18041509 has 8 divisors (see below), whose sum is σ = 18711000. Its totient is φ = 17375232.

The previous prime is 18041497. The next prime is 18041519. The reversal of 18041509 is 90514081.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5189284 + 12852225 = 2278^2 + 3585^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18041509 - 2¹⁷ = 17910437 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 (18041519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21897 + ... + 22705.

It is an arithmetic number, because the mean of its divisors is an integer number (2338875).

Almost surely, 2^18041509 is an apocalyptic number.

It is an amenable number.

18041509 is a deficient number, since it is larger than the sum of its proper divisors (669491).

18041509 is an equidigital number, since it uses as much as digits as its factorization.

18041509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1607.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 18041509 is about 4247.5297526916. The cubic root of 18041509 is about 262.2754372738.

The spelling of 18041509 in words is "eighteen million, forty-one thousand, five hundred nine".