18211 has 2 divisors, whose sum is σ = 18212.
Its totient is φ = 18210.
The previous prime is 18199. The next prime is 18217. The reversal of 18211 is 11281.
It is a strong prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-18211 is a prime.
18211 is a lucky number.
It is a junction number, because it is equal to n+sod(n) for n = 18191 and 18200.
It is not a weakly prime, because it can be changed into another prime (18217) 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 as a sum of consecutive naturals, namely, 9105 + 9106.
It is an arithmetic number, because the mean of its divisors is an integer number (9106).
218211 is an apocalyptic number.
18211 is a deficient number, since it is larger than the sum of its proper divisors (1).
18211 is an equidigital number, since it uses as much as digits as its factorization.
18211 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 16, while the sum is 13.
The square root of 18211 is about 134.9481381865.
The cubic root of 18211 is about 26.3094194406.
Adding to 18211 its reverse (11281), we get a palindrome (29492).
It can be divided in two parts, 182 and 11, that multiplied together give a palindrome (2002).
The spelling of 18211 in words is "eighteen thousand, two hundred eleven".