import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long n = sc.nextLong();
    long ans = -1;
    if(n == 6) ans = 3;
    if(n > 6) { 
      for(long i = 3; i <= 6; i++) {
        if(i != 4) {
          long t = n - i;
          int p = 0;
          while(t % 2 == 0) {
            t /= 2;
            if(t % 2 == 1) p++;
          }
          if(p > 0) {
            ans = i;
            break;
          } 
        }
      }
    }
    System.out.println(ans);
  }
}