#include<iostream.h>
#include<fstream.h>
//using namespace std;
fstream f("factorial.in");
ofstream g("factorial.out");
int n,i,nr;
long p;
int main()
{
	f>>p;
	if(p==0)
		g<<1;
	else
	{
	i=5;
	nr=1;
	do
	{
		i+=5;
		int k=i;
		if((k/5)%5==0)
			while((k/5)%5==0)
			{
				nr++;
				k/=5;
			}
		nr++;
	}
	while(nr<p);
	g<<i;
	}
return 0;
}