# include <fstream>
using namespace std;
int main ()
{
    int p, i, nrz=0, c, n;
    ifstream fin ("fact.in");
    ofstream fout ("fact.out");
    fin>>p;
    if (p==0)
       fout<<"1";
    else
    {
       for (i=5;nrz<p;i+=5)
       {
           c=i, n=i;
           while (c%5==0)
           {
                 nrz++;
                 c/=5;
           }
       }
    
       if (nrz==p)
          fout<<n;
       else
          fout<<"-1";
    }
    return 0; 
}