#include <bits/stdc++.h>

#define NMAX 10010
using namespace std;

ifstream fin("armonica.in");
ofstream fout("armonica.out");

struct fractie
{
   long long x,y;
};

fractie v[NMAX];
long long nr;

int main()
{
   long long sf = 1;
   long long max = 1;
   long long d = 2;
   long long p = 1;
   long long n;

   fin>>nr;

   if(nr%2==0)
      n = nr/2;
   else
      n = nr;

   v[0].x = 1;
   v[0].y = 1;

   while(n>1)
   {
      p = 1;
      while(n%d==0)
      {
         p*=d;
         n/=d;
      }
      sf = max;
      while(p>1)
      {
         v[sf].x = v[0].x * p;
         v[sf].y = v[0].y;
         sf++;

         for(int i = 1;i<max;i++)
         {
            v[sf].x = v[i].x*p;
            v[sf].y = v[i].y;
            sf++;
            v[sf].x = v[i].x;
            v[sf].y = v[i].y*p;
            sf++;
         }
         p/=d;
      }
      d++;
      if(d*d>n)
         d = n;
      max = sf;
   }
   fout<<2*sf-1<<'\n';
   fout<<nr<<" "<<nr<<'\n';
   for(int i=1;i<sf;i++)
   {
      fout<<nr*(v[i].x+v[i].y)/(2*v[i].x)<<" "<<nr*(v[i].x+v[i].y)/(2*v[i].y)<<'\n';
      fout<<nr*(v[i].x+v[i].y)/(2*v[i].y)<<" "<<nr*(v[i].x+v[i].y)/(2*v[i].x)<<'\n';
   }

}