#include <iostream>
#include <fstream>
using namespace std;
int s=5,p,i=1,x,ok=0;;
int main()
{
    ifstream f("fact.in");
    ofstream g("fact.out");
    f>>p;
    while(i<p)
    {
        s=s+5;
        x=s;
        while(x%5==0)
        {
            i++;
            x/=5;
        }
        if(i>p)
            ok++;
    }
    if(ok==0)
        g<<s;
    else
        g<<-1;
    return 0;
}