#include <iostream>
#include <fstream>
#include <math.h>
#define MAX 1e7

using namespace std;

ifstream in("fact.in");
ofstream out("fact.out");

//5 10 15 20
int P;
int all(int k){
    return k/5;
}



int radical(int k){
    int counter = 0 ;
    for(int i = 5; i <= k; i *= 5){
        if(k % i == 0 ){
            counter ++;
        }
    }
    return counter;
}


int F(int j){
    int aux = 0;
    if(j == 0){
        out<<1;
        return 1;
    }
    for(int i = 5 ; i < 900; i += 5){
        aux += radical(i);


        if(aux == j){
            out<<i;
            return i;
        }else if(aux > j){
            out<<-1;
            return -1;
        }

    }
}

int main()
{
    in>>P;
    F(P);

}