#include <fstream>
using namespace std;
ifstream cin("fact.in");
ofstream cout("fact.out");

int main()
{
    int p,ct=0,n=5,x;
    cin>>p;
    if(p==0)
    {
        cout<<1;
        return 0;
    }
    while(ct<p)
    {
        x=n;
        while(x%5==0)
        {
            ct++;
            x/=5;
        }
        n+=5;
    }
    if(p==ct)
        cout<<n-5;
    else
        cout<<-1;
    return 0;
}