#include <cstdio>

using namespace std;
int p,i=0,x=0;
int divz(int n)
{
    int k=0;
    while(n%5==0)
    {
              k++;
              n=n/5;
    }
    return k;
}


int main()
{ 
    freopen("fact.in","r",stdin);
    freopen("fact.out","w",stdout);
    scanf("%d",&p);
    while(i<p)
    {
              x=x+5;
              if(x%25==0)i=i+divz(x);
                                  else i++;
    }
     if(p==0)printf("-1");
     else
         if(i==p) printf("%d",x);
              else printf("-1");

}