#include <fstream>
using namespace std;
ifstream fin("fact.in");
ofstream fout("fact.out");
int n,p,i,x;
int main()
{
    fin>>n;
    if (n==0)fout<<1;
    else
    {

        for(i=0,p=5; i<n;p+=5)
         {
             x=p;
             while(x%5==0){i++;x/=5;}

         }
         if (i==n) fout<< p-5;
         else fout<<-1;
    }

}