#include<stdio.h>

int a[13];
int b[13];

int i,x, ok, ok2,p;
long n;

int main()
{
	freopen("fact.in","r",stdin);
	freopen("fact.out","w",stdout);
	b[0]=1;
	for (i=1; i<=12; i++)
		b[i]=b[i-1]*5;
	a[0]=0;
	for (i=1; i<=12; i++)
		a[i]=a[i-1]+b[i-1];
	scanf("%ld",&p);
	if (p==0) 
	{
		ok2=0; printf("1\n");
	}
	else ok2=1;
	n=0; ok=1;
	while (p!=0 && ok)
		for (i=1; i<=12; i++)
			if (a[i]<=p && a[i+1]>p)
			{
				x=p/a[i];
				if (x>4) ok=0;
				n+=x*b[i];
				p-=x*a[i];
				break;
			}
	if (ok && ok2) 
		printf("%ld\n",n);
	else
		if (ok2)
			printf("-1\n");
    fclose(stdin); fclose(stdout);
	return 0;
}