1 #include<cstdio>
  2 #include<cstdlib>
  3 #include<cstring>
  4 #include<iostream>
  5 #include<algorithm>
  6 #include<queue>
  7 using namespace std;
  8 #define Maxn 200010
  9 #define Maxm 200010
 10 #define INF 0xfffffff
 11 #define LL long long
 12
 13 int mymin(int x,int y) {return x<y?x:y;}
 14
 15 struct node
 16 {
 17     int x,y,f,c,o,next;
 18 }t[Maxm*2];
 19 int first[Maxn],len;
 20
 21 int st,ed;
 22 void ins(int x,int y,int f,int c)
 23 {
 24     if(c<=0&&x!=st&&y!=ed) return;
 25     t[++len].x=x;t[len].y=y;t[len].f=f;t[len].c=c;
 26     t[len].next=first[x];first[x]=len;t[len].o=len+1;
 27     t[++len].x=y;t[len].y=x;t[len].f=0;t[len].c=-c;
 28     t[len].next=first[y];first[y]=len;t[len].o=len-1;
 29 }
 30
 31 queue<int > q;
 32 bool inq[Maxn];
 33 LL dis[Maxn],flow[Maxn];
 34 int pre[Maxn];
 35 bool bfs()
 36 {
 37     memset(inq,0,sizeof(inq));
 38     // memset(dis,63,sizeof(dis));
 39     for(int i=1;i<=ed;i++) dis[i]=-INF;
 40     while(!q.empty()) q.pop();
 41     q.push(st);dis[st]=0;flow[st]=INF;
 42     inq[st]=1;
 43     while(!q.empty())
 44     {
 45         int x=q.front();
 46         for(int i=first[x];i;i=t[i].next) if(t[i].f>0)
 47         {
 48             int y=t[i].y;
 49             if(dis[y]<dis[x]+t[i].c)
 50             {
 51                 dis[y]=dis[x]+t[i].c;
 52                 flow[y]=mymin(flow[x],t[i].f);
 53                 pre[y]=i;
 54                 if(!inq[y])
 55                 {
 56                     inq[y]=1;
 57                     q.push(y);
 58                 }
 59             }
 60         }
 61         q.pop();inq[x]=0;
 62     }
 63     return dis[ed]>-INF;
 64 }
 65
 66 LL sum;
 67 void max_flow()
 68 {
 69     while(bfs())
 70     {
 71         if(dis[ed]<0) return;
 72         sum+=flow[ed]*dis[ed];
 73         int x=ed;
 74         while(x!=st)
 75         {
 76             t[pre[x]].f-=flow[ed];
 77             t[t[pre[x]].o].f+=flow[ed];
 78             x=t[pre[x]].x;
 79         }
 80     }
 81 }
 82
 83 int n;
 84 LL pri[Maxn];int pl;
 85 LL as[Maxn];
 86 bool vis[Maxn];
 87 void init()
 88 {
 89     memset(vis,0,sizeof(vis));
 90     for(int i=2;i<=n;i++)
 91     {
 92         if(!vis[i]) pri[++pl]=i;
 93         for(int j=1;j<=pl;j++)
 94         {
 95             if(i*pri[j]>n) break;
 96             vis[i*pri[j]]=1;
 97             if(i%pri[j]==0) break;
 98         }
 99     }
100     for(int i=1;i<=pl;i++)
101     {
102         as[i]=pri[i];
103         while(as[i]*pri[i]<=n) as[i]*=pri[i];
104         sum+=as[i];
105     }
106     int i;
107     for(i=1;pri[i]*pri[i]<n&&i<=pl;i++)
108      for(int j=pl;pri[j]*pri[j]>=n;j--)
109      {
110          int x=pri[i]*pri[j];
111          if(x>n) continue;
112          while(x*pri[i]<=n) x*=pri[i];
113          ins(i,j,1,x-as[i]-as[j]);
114      }
115     st=pl+1;ed=st+1;
116     for(int i=1;pri[i]*pri[i]<n&&i<=pl;i++)
117         ins(st,i,1,0);
118     for(int i=pl;pri[i]*pri[i]>=n;i--) ins(i,ed,1,0);
119 }
120
121 int main()
122 {
123     len=0;
124     memset(first,0,sizeof(first));
125     sum=0;
126     scanf("%d",&n);
127     init();
128     max_flow();
129     printf("%lld\n",sum+1);
130     return 0;
131 }