#include <stdio.h>

int ans[] = {
    0,11,23,31,41,53,61,71,83,97,101,113,127,131,149,151,163,173,181,191,2011,211,223,233,241,251,263,271,281,293,307,311,3217,331,347,353,367,373,383,397,401,419,421,431,443,457,461,479,487,491,503,5113,521,5323,541,557,563,571,587,593,601,613,6211,631,641,653,661,673,683,691,701,719,727,733,743,751,761,773,787,797,809,811,821,839,8419,853,863,877,881,8923,907,911,929,937,941,953,967,971,983,991,1009
};

int main() {
    int in;
    scanf("%d", &in);
    printf("%d", ans[in]);
    return 0;
}