#include <stdio.h>

FILE* f;
FILE* s;

int main()
{

	f=fopen ("fact.in","r");
	s=fopen ("fact.out","w");

	long int n;
	fscanf (f,"%ld",&n);

	for (long int i=1;i<=99999999;i++)
	{

		long int j=i;
		long int c=0;
		long int f=5;
		while (f<=j)
		{
			c=c+(j/f);
			f=f*5;
		}

		if (c==n)
		{
			fprintf (s,"%ld ",i);
            break;
		}

	}

	fcloseall();

	return 0;

}