#include <fstream>
#include <cmath>
#define INF 1500000
 
using namespace std;
 
bool prim[INF];
 
int main(){
ifstream fin("prim.in");
ofstream fout("prim.out");
long long n,k,nrp,i,j;
fin>>k;
for(i=2;i<INF;i++)
  prim[i]=1;
for(i=2,nrp=0;i<=INF;i++)
  if(prim[i]){
    if(++nrp==k+1){
      n=(long long)i*i;
      fout<<n;
      fout.close();
      return 0;
    }    
    for(j=i;j<=INF;j+=i)
      prim[j]=0;
  }
}