This might come off as pessimistic, but I would hesitate to consider any department a "safety" school...especially in the top 20. I understand that you feel like you have a strong application and are feeling confident which is great since the application cycle can be incredibly stressful. That being said there are a lot of things outside of your control that go into application evaluations. I can assure you that nobody is going to worry about a misplaced application, especially considering you will need letters of recommendation as a part of your package.