2218 has 4 divisors (see below), whose sum is σ = 3330.
Its totient is φ = 1108.
The previous prime is 2213. The next prime is 2221. The reversal of 2218 is 8122.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in only one way, i.e., 2209 + 9 = 47^2 + 3^2
It is a Smith number, since the sum of its digits (13) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.
It is a plaindrome in base 12, base 15 and base 16.
It is a junction number, because it is equal to n+sod(n) for n = 2198 and 2207.
It is not an unprimeable number, because it can be changed into a prime (2213) by changing a digit.
2218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 553 + ... + 556.
2218 is a deficient number, since it is larger than the sum of its proper divisors (1112).
2218 is a wasteful number, since it uses less digits than its factorization.
2218 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1111.
The product of its digits is 32, while the sum is 13.
The square root of 2218 is about 47.0956473573.
The cubic root of 2218 is about 13.0412888435.
The spelling of 2218 in words is "two thousand, two hundred eighteen".