#include <stdio.h>

int main() {
	freopen("fact.in","r",stdin);
	freopen("fact.out","w",stdout);
	
	int n;
	
	scanf("%d",&n);
	
	int nrz = 0;
	int nr = 0;
	
	for (int i = 5 ; nrz < n ; i +=5) {
		int j = i;
		while (j % 5 == 0) {
			j /= 5;
			nrz++;
		}
		nr = i;
	}
	
	if (nrz == n) {
		printf("%d",nr);
	} else {
		printf("-1");
	}
	
	return 0;
}