#include <iostream>
#include<fstream>
using namespace std;
ifstream f("factorial.in");
ofstream g("factorial.out");
int main()
{
    long p,i,nr;
    f>>p;
    nr=-1;
    if((p-5)%6==0)
    g<<"-1";
    else
    {
    for(i=-1;i<=p;i=i+6)
    {
        nr++;
    }
    g<<(p-nr)*5;}
    return 0;
}