18003 has 8 divisors (see below), whose sum is σ = 25488. Its totient is φ = 11264.

The previous prime is 17989. The next prime is 18013. The reversal of 18003 is 30081.

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 18003 - 2⁴ = 17987 is a prime.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 18003.

It is not an unprimeable number, because it can be changed into a prime (18013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126 + ... + 227.

It is an arithmetic number, because the mean of its divisors is an integer number (3186).

2¹⁸⁰⁰³ is an apocalyptic number.

18003 is a deficient number, since it is larger than the sum of its proper divisors (7485).

18003 is a wasteful number, since it uses less digits than its factorization.

18003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 18003 is about 134.1752585241. The cubic root of 18003 is about 26.2088698287.

Adding to 18003 its reverse (30081), we get a palindrome (48084).

The spelling of 18003 in words is "eighteen thousand, three".