#include <fstream>
using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
int main()
{
    int p,n,ni=0;
    f>>p;
    if(p==0)g<<1;
    else{
        p--;
        for(n=5;p!=0;n+=5){
            if(n%25==0){
                ni=n;
                while(ni%5==0){
                    ni/=5;
                    p--;}}
            else
            {
                while(n%25!=0){
                        n+=5;p--;}}
        g<<n;
    }}
}