#include<fstream>
using namespace std;
int main()
{unsigned long long n, p, c, u, d;
ifstream f("fact.in");
ofstream h("fact.out");
f>>p;
if (p==0)
	n=1;
else
{c=1;
u=5;
while (c<p)
{u=u+5;
d=u;
if (d%25==0)
do
{d=d/5;
c=c+1;}
while (d%5==0);
else
	c=c+1;
}
n=u;
}
if (c>p)
	h<<"-1"<<endl;
else
	h<<n<<endl;

f.close();
h.close();
return 0;
}