版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/wwwlps/article/details/84193513
#include <iostream>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <map>
#include <queue>
#include <stack>
#include <vector>
#include <set>
#define LL long long
#define INF 0x3f3f3f3f
using namespace std;
const int mod=1000000007;
const int maxn=205;
const int inv=500000004;
LL n;
LL ms(LL x)
{
x %= mod;
return (x * (x + 1) % mod) * inv % mod;
}
void solve()
{
LL t=n;
vector<LL>v;
for(int i=2;i<=sqrt(n);i++)
{
if(t%i==0)
{
v.push_back(i);
while(t%i==0)
{
t/=i;
}
}
}
if(t>1)
v.push_back(t);
int len=v.size();
LL ans=0;
for(int i=1;i<(1<<len);i++)
{
int cnt=0;
LL temp=1;
for(int j=0;j<len;j++)
{
if((i>>j)&1)
{
cnt++;
temp*=v[j];
}
}
LL num=n/temp;
if(cnt&1)
{
ans = (ans + (temp%mod) * ms(num) % mod) % mod;
}
else
{
ans=(ans- (temp%mod) * ms(num) % mod+mod)%mod;
}
}
cout << ans << endl;
}
int main()
{
while(cin>>n)
{
solve();
}
return 0;
}
#include <iostream>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <map>
#include <queue>
#include <stack>
#include <vector>
#include <set>
#define INF 0x3f3f3f3f
#define LL long long
using namespace std;
const int mod=1e9+7;
const int maxn=1e5+5;
const int inv=5e8+4;
LL n;
LL phi(LL n)
{
LL ans=n;
for(LL i=2;i<=sqrt(n);i++)
{
if(n%i==0)
{
ans=ans/i*(i-1);
while(n%i==0)
{
n/=i;
}
}
}
if(n>1)
ans=ans/n*(n-1);
return ans;
}
int main()
{
ios::sync_with_stdio(false);
//cout << phi(100000000000000) << endl;
while(cin>>n)
{
LL t=n;
t%=mod;
LL ans=((t*(t+1)%mod-(t*(phi(n)%mod))%mod+mod)%mod)*inv;
ans%=mod;
cout << ans << endl;
}
return 0;
}