#include <fstream>

using namespace std;
ifstream fin("prim.in");
ofstream fout("prim.out");
long long i,j,k,l;
char c[1500001];
int main()
{
    fin>>k; i=1;
    while(l!=k+1)
    {
        i++;
        if(c[i]==0)
        {
            l++;
            if(l!=k+1)
            {
                for(j=i*i;j<=1500000;j=j+i)
                    c[j]=1;
            }
        }
    }
    fout<<i*i;
    return 0;
}