#include <iostream>
#include <fstream>
#define MAX 100000000

using namespace std;

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

//5 10 15 20
int P;
int zece(int k){
    return k/10;
}
int cinci(int k){
    return k/5-zece(k);
}
int all(int k){
    return zece(k) + cinci(k);
}
int F(int j){
    int counter = 0;
    if(P == 0){
        out<<1;
        return 1;
    }
    for(int i = 0 ; i < MAX; i ++){
        int a = all(i);
        if(i % 25 == 0 && i ){
            counter ++;
        }

        if(a + counter == j){
            out<<i;
            return i;
        }

    }
    out<<"-1";
    return -1;

}

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

    //for(int i = 0 ; i < 1000; i ++){
    //    cout<<i<<" "<<F(i)<<endl;
    //}

}