223 (two hundred [and] twenty-three) is the natural number between 222 and 224.
223 is a prime number. It is the smallest prime for which the two nearest primes on either side of it are 16 units apart. Among the 720 permutations of the numbers from 1 to 6, exactly 223 of them have the property that at least one of the numbers is fixed in place by the permutation and the numbers less than it and greater than it are separately permuted among themselves.
In connection with Waring's problem, 223 requires the maximum number of terms (37 terms) when expressed as a sum of positive fifth powers, and is the only number that requires that many terms.