#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> P;

#define fi first
#define se second
#define repl(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
#define rep(i,n) repl(i,0,n)
#define all(x) (x).begin(),(x).end()
#define dbg(x) cout<<#x"="<<x<<endl
#define mmax(x,y) (x>y?x:y)
#define mmin(x,y) (x<y?x:y)
#define maxch(x,y) x=mmax(x,y)
#define minch(x,y) x=mmin(x,y)
#define uni(x) x.erase(unique(all(x)),x.end())
#define exist(x,y) (find(all(x),y)!=x.end())
#define bcnt __builtin_popcount

#define INF 1e16
#define mod 1000000007

int n;
vector<int> ps,sps;
int mask[2000];
vector<int> vs[2000];
int dp[2][1<<12];

int main(){
  cin>>n;

  repl(i,2,n+1){
    bool ok=true;
    repl(j,2,i){
      if(i%j==0)ok=false;
    }
    if(ok)ps.push_back(i);
  }
  rep(i,ps.size()){
    if(ps[i]*ps[i]<=n)sps.push_back(ps[i]);
  }
  int m=sps.size();

  repl(i,2,n+1){
    rep(j,m){
      if(i%sps[j]==0)mask[i]|=(1<<j);
    }
    int mxp=-1;
    rep(j,ps.size()){
      if(i%ps[j]==0)maxch(mxp,ps[j]);
    }
    vs[mxp].push_back(i);
  }

  memset(dp,-1,sizeof(dp));
  int crt=0,nxt=1;
  dp[crt][0]=0;
  repl(i,2,n+1){
    if(vs[i].size()==0)continue;
    memset(dp[nxt],-1,sizeof(dp[nxt]));
    for(int v : vs[i]){
      rep(j,1<<m){ 
        if((j&mask[v])==0)maxch(dp[nxt][j^mask[v]],dp[crt][j]+v);
        maxch(dp[nxt][j],dp[crt][j]);
      }
    }
    swap(crt,nxt);
  }

  cout<<*max_element(dp[crt],dp[crt]+(1<<m))<<endl;

  return 0;
}