18009518 has 16 divisors (see below), whose sum is σ = 28103856. Its totient is φ = 8648640.

The previous prime is 18009503. The next prime is 18009521. The reversal of 18009518 is 81590081.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3530 + ... + 6962.

It is an arithmetic number, because the mean of its divisors is an integer number (1756491).

Almost surely, 2^18009518 is an apocalyptic number.

18009518 is a deficient number, since it is larger than the sum of its proper divisors (10094338).

18009518 is a wasteful number, since it uses less digits than its factorization.

18009518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3539.

The product of its (nonzero) digits is 2880, while the sum is 32.

The square root of 18009518 is about 4243.7622459323. The cubic root of 18009518 is about 262.1203242750.

Adding to 18009518 its reverse (81590081), we get a palindrome (99599599).

The spelling of 18009518 in words is "eighteen million, nine thousand, five hundred eighteen".