public override bool Equals(object obj)
        {
            var objAsNum = obj as BitArray64;

            if (objAsNum == null)
            {
                return false;
            }

            return this.number == objAsNum.number;
        }

....................................

  public static bool operator ==(BitArray64 first, BitArray64 second)
        {
            return first.Equals(second);
        }