18203 has 4 divisors (see below), whose sum is σ = 18480. Its totient is φ = 17928.

The previous prime is 18199. The next prime is 18211. The reversal of 18203 is 30281.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 30281 = 107 ⋅283.

It is a cyclic number.

It is not a de Polignac number, because 18203 - 2² = 18199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18223) 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, 26 + ... + 192.

It is an arithmetic number, because the mean of its divisors is an integer number (4620).

2¹⁸²⁰³ is an apocalyptic number.

18203 is a deficient number, since it is larger than the sum of its proper divisors (277).

18203 is a wasteful number, since it uses less digits than its factorization.

18203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 18203 is about 134.9184939139. The cubic root of 18203 is about 26.3055663448.

Adding to 18203 its reverse (30281), we get a palindrome (48484).

It can be divided in two parts, 1820 and 3, that multiplied together give a triangular number (5460 = T₁₀₄).

The spelling of 18203 in words is "eighteen thousand, two hundred three".