#include <fstream>

using namespace std;
ifstream in("fact.in");
ofstream out("fact.out");
int pas=1<<20;
int main()
{
    int p,n=0,i=0,x;
    in >> p;
    x=p+1;
    if(x%6==0) out << -1;
    else
    {
        while(pas)
        {
            if(i+pas<=5*p)
                i+=pas;
            pas/=2;
        }
        out << i;
    }
    return 0;
}