#include<stdio.h>
#include<fstream.h>

int main()  
{
long p,n,tt,t,k5=0;  
//ifstream in("fact.in");  
//ofstream out("fact.out");  
freopen("fact.in","r",stdin);  
freopen("fact.out","w",stdout);  
scanf("%ld ",&p);  
//in>>p;  
//in.close();  

if(p==0)  
//out<<"1";  
printf("1");
else  
{t=0;  
do {  
t+=5;  
tt=t;  
while(tt%5==0)  
{tt=tt/5;  
                k5++;}  
      }while(k5!=p);  
   
 //out<<t;}  
 //out.close();  
 printf("%ld",t);
}
 return 0;  
 }