#include <fstream>

using namespace std;

int main()
{
    int p,k,y,x,n,i,r;
    ifstream f("factorial.in");
    ofstream g("factorial.out");
    f>>p;
    n=1;
    y=n;
    for (i=1;i<=100000000;i++)
    {
        k=0;
        x=y;
        while (x)
        {
           r=x%10;
           if (r==0)
           {
               k++;
           }
           x=x/10;
           if (x%10!=0)
           {
               break;
           }
        }
        if (k==p)
        {
            g<<n;
            break;
        }
        y=n*(n+1);
        n+=1;
    }
    if (k!=p)
    {
        g<<"-1";
    }
    f.close();
    g.close();
    return 0;
}