18355 has 4 divisors (see below), whose sum is σ = 22032.
Its totient is φ = 14680.
The previous prime is 18353. The next prime is 18367. The reversal of 18355 is 55381.
It is a semiprime because it is the product of two primes.
It is not a de Polignac number, because 18355 - 21 = 18353 is a prime.
It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.
It is a Duffinian number.
It is a plaindrome in base 15.
It is not an unprimeable number, because it can be changed into a prime (18353) 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, 1831 + ... + 1840.
It is an arithmetic number, because the mean of its divisors is an integer number (5508).
218355 is an apocalyptic number.
18355 is a deficient number, since it is larger than the sum of its proper divisors (3677).
18355 is an equidigital number, since it uses as much as digits as its factorization.
18355 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 3676.
The product of its digits is 600, while the sum is 22.
The square root of 18355 is about 135.4806259212.
The cubic root of 18355 is about 26.3785830281.
It can be divided in two parts, 18 and 355, that added together give a palindrome (373).
The spelling of 18355 in words is "eighteen thousand, three hundred fifty-five".