18201 has 4 divisors (see below), whose sum is σ = 24272.
Its totient is φ = 12132.
The previous prime is 18199. The next prime is 18211. The reversal of 18201 is 10281.
Adding to 18201 its reverse (10281), we get a palindrome (28482).
It is a happy number.
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 18201 - 21 = 18199 is a prime.
It is a D-number.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (18211) 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 3 ways as a sum of consecutive naturals, for example, 3031 + ... + 3036.
It is an arithmetic number, because the mean of its divisors is an integer number (6068).
218201 is an apocalyptic number.
It is an amenable number.
18201 is a deficient number, since it is larger than the sum of its proper divisors (6071).
18201 is an equidigital number, since it uses as much as digits as its factorization.
18201 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 6070.
The product of its (nonzero) digits is 16, while the sum is 12.
The square root of 18201 is about 134.9110818280.
The cubic root of 18201 is about 26.3046028945.
The spelling of 18201 in words is "eighteen thousand, two hundred one".