This problem is a programming version of Problem 70 from projecteuler.net
Euler's Totient function, [sometimes called the phi function], is used to determine the number of positive numbers less than or equal to which are relatively prime to . For example, as and are all less than nine and relatively prime to nine, .
The number 1 is considered to be relatively prime to every positive number, so . Interestingly, , and it can be seen that is a permutation of .
Find the value of , , for which is a permutation of and the ratio produces a minimum.
Input Format
Input contains an integer
Constraints
Output Format
Print the answer corresponding to the test case.
Sample Input
100
Sample Output
21