/*
#include <fstream>//varianta I  100p
using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
int s,i,n,m,mij,z,fact5,st,dr;
int main()
{
    f>>n;st=1;dr=500000000;
    while(st<=dr){
    mij=(st+dr)/2;
    m=mij;
    z=0;fact5=5;
    while(m>=fact5){z+=m/fact5;fact5*=5;}
    if(z==n)break;
      else if(z>n)dr=mij-1;
         else st=mij+1;
    }
    mij=mij-mij%5;
    if(n==0)g<<1<<'\n';
    else
    if(st<=dr)  g<<mij<<'\n';
    else g<<-1<<'\n';
    g.close();
    return 0;
}
*/
#include <fstream>//varianta II 50p
using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
int s,i,n,x,k;
int main()
{
    f>>n;
    for(i=5;i<=30000000;i+=5){
       x=i;
       x/=5;
       k++;
       while(x%5==0){x/=5;k++;}
       if(k>=n)break;
    }
    if(k==n)  g<<i<<'\n';
    else g<<-1<<'\n';
    g.close();
    return 0;
}