#include<cstdio>
#include<ctime>
int f,p,g;
clock_t start,end;
FILE *in,*out;
int main()
{
	start=clock();
	in=fopen("fact.in","r");
	fscanf(in,"%d",&p);
	out=fopen("fact.out","w");
	if(p==0)fputc('1',out);
	else
	{
	 do
	 {
		f+=5;g=f;
		while(g%5==0){p--;g/=5;}
	 }while(p>0);
	 if(p==0)fprintf(out,"%d",f);
	  else fputs("-1",out);
	}
	end=clock();
	printf("%f",(float)(end-start)/CLK_TCK);
}