18533 has 4 divisors (see below), whose sum is σ = 19008. Its totient is φ = 18060.

The previous prime is 18523. The next prime is 18539. The reversal of 18533 is 33581.

18533 is nontrivially palindromic in base 9.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 18533 - 2⁴ = 18517 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18539) 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, 173 + ... + 258.

It is an arithmetic number, because the mean of its divisors is an integer number (4752).

2¹⁸⁵³³ is an apocalyptic number.

It is an amenable number.

18533 is a deficient number, since it is larger than the sum of its proper divisors (475).

18533 is an equidigital number, since it uses as much as digits as its factorization.

18533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474.

The product of its digits is 360, while the sum is 20.

The square root of 18533 is about 136.1359614503. The cubic root of 18533 is about 26.4635787783.

It can be divided in two parts, 185 and 33, that multiplied together give a triangular number (6105 = T₁₁₀).

The spelling of 18533 in words is "eighteen thousand, five hundred thirty-three".