#include<bits/stdc++.h>
using namespace std;
using Int = long long;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}

//INSERT ABOVE HERE
const int MAX = 1e7;
int dp[MAX]={};
int ok[MAX]={};

signed main(){
  for(int i=2;i<MAX;i++)
    if(!dp[i]) for(int j=i;j<MAX;j+=i) dp[j]=i;
  int n;
  cin>>n;
  for(int i=2;i<MAX;i++){
    if(dp[i/dp[i]]==i/dp[i]&&i/dp[i]!=dp[i]) ok[i]=1;
    if(i/dp[i]==(long long)dp[i]*dp[i]) ok[i]=1;
  }
  
  for(int i=2;i<MAX;i++){
    if(!ok[i]) continue;
    n--;
    if(n==0){
      cout<<i<<endl;
      break;
    }
  }
  return 0;
}