代码：

 1 #include <cstdio>
 2 #include <iostream>
 3 #include <cstring>
 4 #include <algorithm>
 5 #include <cmath>
 6 #include <cctype>
 7 #include <vector>
 8 using namespace std;
 9 
10 #define LL long long
11 #define res register long long
12 inline LL read()
13 {
14     LL x(0),f(1); char ch;
15     while(!isdigit(ch=getchar())) if(ch=='-') f=-1;
16     while(isdigit(ch)) x=x*10+ch-'0',ch=getchar();
17     return f*x;
18 }
19 LL s[10000000],tot;
20 LL b[10000000],cnt;
21 inline void pre_work(LL n)
22 {
23     //质因数 
24     LL tmp=n;
25     for(res i=2 ; i*i<=n ; i++)
26     {
27         if(n%i==0) s[++tot]=i;
28         while(n%i==0) n/=i;
29     }
30     if(n>1) s[++tot]=n;
31     //约数 
32     for(res i=1 ; i*i<=tmp ; i++)
33         if(tmp%i==0)
34         {
35             b[++cnt]=i;
36             if(i!=tmp/i) b[++cnt]=tmp/i;
37         }
38 }
39 
40 LL phi(LL n)
41 {
42     LL ans=n;
43     for(res i=1 ; i<=tot ; i++)
44     {
45         if(n%s[i]==0) 
46             ans=ans/s[i]*(s[i]-1);
47     }
48     return ans;
49 }
50 
51 int main()
52 {
53 //    freopen("gcd.in","r",stdin);
54 //    freopen("gcd.out","w",stdout);
55     LL n;
56     n=read();
57     pre_work(n);
58     sort(b+1,b+cnt+1);
59     for(res i=1 ; i<=cnt ; i++)
60     {
61         cout<<b[i]<<" ";
62         cout<<phi(n/b[i])<<endl;
63     }
64     return 0;
65 }

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