#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn = 2000000+100;
ll poww(ll a,ll b)
{
ll res = 1;
ll base = a;
while(b)
{
if(b&1) res *= base;
base *= base, b>>=1;
}
return res;
}
inline ll f(ll p,int e) ///填函数在质数幂次处的表达式
{
if(p==1||e==0) return 1;
///return f(p^e)
ll res = poww(p,e);
return res*res+3*res+1;
}
ll pow_sum(ll n,int k) ///幂和函数（如果需要更高次的话可以在这里添加）
{
///return sum(i^k),i from 1 to n.
if(k==0) return n;
if(k==1) return n*(n+1)/2;
if(k==2) return n*(n+1)*(2*n+1)/6;
}
ll f_p[maxn][3];///F_prime(id(n/i))
ll n;
int n_2; ///(int)sqrt(n)
int n_3; ///(int)pow(n,1.0/3.0)
int n_6; ///(int)pow(n,1.0/6.0)
ll val_id[maxn]; ///give the id, return the id-th number like 'n/i' ,(val_id[1] = 1)
int val_id_num; ///how many numbers like 'n/i'
int val_id_num_3; ///how many numbers like 'n/i' below n/n_3;
int p[200000+100];
bool isp[maxn];
int p_sz_2; ///pi(n_2)
int p_sz_3; ///pi(n_3)
int p_sz_6; ///pi(n_6)
void init()
{
n_2 = (int)sqrt(n);
n_3 = (int)pow(n,1.0/3.0);
n_6 = (int)pow(n,1.0/6.0);
val_id_num = 0;
for(ll i=1; i<=n;)
{
val_id[++val_id_num] = i;
if(i==n) break;
i = n/(n/(i+1));
}
memset(isp,1,sizeof isp);
isp[1] = 0;
for(int i=2; i<=n_2; i++)
{
if(isp[i])
{
p[++p_sz_2] = i;
if(i<=n_3) p_sz_3++;
if(i<=n_6) p_sz_6++;
}
for(int j=1; j<=p_sz_2&&p[j]*i<=n_2; j++)
{
isp[i*p[j]] = 0;
if(i%p[j]==0) break;
}
}
}
inline int get_id(ll k) ///give a number like 'n/i', return the id of it
{
if(k>n_2) return val_id_num-n/k+1;
else return k;
}
ll c[maxn];
int lowbit(int n)
{
return n & (-n);
}
void add(int x,ll d)
{
while(x<maxn)
{
c[x]+=d;
x+=lowbit(x);
}
}
ll sum(int x)
{
ll ans=0;
while(x)
{
ans+=c[x];
x-=lowbit(x);
}
return ans;
}
struct node
{
int k_max;
ll val,f_val;
};
void update_bfs(int k,int type)
{
queue<node> q;
while(!q.empty()) q.pop();
int e = 1;
for(ll i=p[k]; i<n/n_3; i*=p[k])
{
node st;
st.k_max = k;
st.val = i;
if(type==-1) st.f_val = f(p[k],e);
else st.f_val = poww(i,type);
q.push(st), e++;
}
while(!q.empty())
{
node hd = q.front();
q.pop();
if((hd.val!=p[hd.k_max]&&type>=0)||type==-1)
{ //if(type==-1)cout << "****" << hd.val << "****" << hd.f_val << endl;
ll w = n/hd.val;
w = n/w; //cout << hd.val << "[" << w<<" , " << val_id[val_id_num] << "]" << endl;
if(type==-1)
{
add(get_id(w),hd.f_val);
add(val_id_num+1,-1ll*hd.f_val);
}
else
{
add(get_id(w),-1ll*hd.f_val);
add(val_id_num+1,hd.f_val);
}
}
for(int i=hd.k_max+1; hd.val*p[i]<n/n_3&&i<=p_sz_2; i++)
{
ll res = p[i];
for(int e=1;; e++)
{
if(hd.val*res<n/n_3)
{
node nxt;
nxt.k_max = i;
nxt.val = hd.val*res;
if(type==-1) nxt.f_val = hd.f_val*f(p[i],e);
else nxt.f_val = hd.f_val*poww(res,type);
q.push(nxt);
}
else break;
res *= p[i];
}
}
}
}
void get_f_p(ll n,int times)
{
for(int i=1; i<=val_id_num; i++)
{
for(int j=0; j<=times; j++)
{
f_p[i][j] = pow_sum(val_id[i],j)-1;
}
}
int now;
//for(now=1;now<=p_sz_2;now++){
for(now=1; p[now]<=n_6; now++){
for(int j=val_id_num; j>=1; j--)
{
ll w = val_id[j]/p[now];
if(w<p[now]) break;
ll val=1;
for(int k = 0; k<=times; k++)
{
f_p[j][k] = f_p[j][k] - val*(f_p[get_id(w)][k]-f_p[p[now-1]][k]);
val *= p[now];
}
}
}
int nnow = now;
int val = 1;
for(int tt = 0; tt<=times; tt++)
{
now = nnow;
memset(c,0,sizeof c);
add(1,f_p[1][tt]);
for(int i=2; val_id[i]<n/n_3; i++) add(i,f_p[i][tt] - f_p[i-1][tt]);
for(; p[now]<=n_3; now++)
{
for(int j=val_id_num; j>=1; j--)
{
ll w = val_id[j]/p[now];
if(val_id[j]<n/n_3) break;
if(w<p[now]) break;
if(w<n/n_3) f_p[j][tt] = f_p[j][tt] - (sum(get_id(w)) - sum(p[now-1]))*poww(p[now],tt);
else f_p[j][tt] = f_p[j][tt] - (f_p[get_id(w)][tt]-sum(p[now-1]))*poww(p[now],tt);
}
update_bfs(now,tt);
}
for(int i=1; i<=val_id_num&&val_id[i]<n/n_3; i++) f_p[i][tt] = sum(i);
for(; now<=p_sz_2; now++)
{
for(int j=val_id_num; j>=1; j--)
{
ll w = val_id[j]/p[now];
if(val_id[j]<n/n_3) break;
if(w<p[now]) break;
f_p[j][tt] -= (f_p[get_id(w)][tt]-f_p[p[now-1]][tt])*poww(p[now],tt);
}
}
}
for(int i=1; i<=val_id_num; i++)
{
///f_p[][0/1/2/3/...]分别代表质数个数/质数和/质数平方和/质数三次方和/...根据自己需要添加
///if f(p) = p^2+3p+1,then write:f_p[i][0] = f_p[i][2] + 3*f_p[i][1] + f_p[i][0];
f_p[i][0] = f_p[i][2] + 3*f_p[i][1] + f_p[i][0];
}
}
ll F[2000000+100];
void get_f_3(ll n) ///V(F_{pi(n^(1/3))+1},n)
{
ll q = p[p_sz_3+1];
for(int now=1; now<=val_id_num; now++)
{
if(val_id[now]<q) F[now] = 1;
else if(val_id[now]<q*q) F[now] = 1+(f_p[now][0]-f_p[q-1][0]);
else
{
F[now] = 1+(f_p[now][0]-f_p[q-1][0]);
for(int pp=p_sz_3+1; p[pp]<=(int)(sqrt(val_id[now]))&&pp<=p_sz_2; pp++)
{
F[now] += f(p[pp],2) + (f(p[pp],1))*(f_p[get_id(val_id[now]/p[pp])][0]-f_p[get_id(p[pp])][0]);
}
}
}
}
void get_f_6(ll n) ///V(F_{pi(n^(1/6))+1},n)
{
memset(c,0,sizeof c);
add(1,F[1]);
for(int i=2; val_id[i]<n/n_3; i++) add(i,F[i] - F[i-1]);
for(int k=p_sz_3; k>p_sz_6; k--)
{
int now = val_id_num;
for(; val_id[now]>=n/n_3; now--)
{
int e = 1;
ll _p = p[k];
while(val_id[now]/_p)
{
if(val_id[now]/_p>=n/n_3) F[now] += F[get_id(val_id[now]/_p)]*f(p[k],e);
else F[now] += sum(get_id(val_id[now]/_p))*f(p[k],e);
_p *= p[k], e++;
}
}
if(k==1) break;
//cout << "******" << p[k] << "******" << n/n_3 << endl;
update_bfs(k,-1);///bfs to update [lpf(i)==P{k-1}]f(i)
}
for(int i=1; i<=val_id_num&&val_id[i]<n/n_3; i++) F[i] = sum(i);
}
void get_f(ll n)
{
for(int k=p_sz_6; k>=1; k--)
{
for(int now = val_id_num; now>=1; now--)
{
int e = 1;
ll _p = p[k];
while(val_id[now]/_p)
{
F[now] += F[get_id(val_id[now]/_p)]*f(p[k],e);
_p *= p[k], e++;
}
}
}
}
int main() //n = 1000000000; //1e10:455052511,0.83s/0.58s 1e12:37607912018 9.224s/5.105s
{
cin >> n;
init();
get_f_p(n,2);
get_f_3(n);
get_f_6(n);
get_f(n);
//for(int i=1; i<=val_id_num; i++) cout << val_id[i] << " : " << F[i] << endl;
cout << F[val_id_num] << endl;
return 0;
}
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