Dressing can be very hi calorie, so be careful on that one. It's one area people tend to underestimate their calorie intake.
As far as the formula you calculated, the point of the calculation is to tell you that based on your current age/weight/height and activity, how many calories a day you would have to eat to maintain your current weight.
So if you ate 3598 calories a day exercising as much as you do, then you'd stay at your current weight.
The idea is to use that number to figure out how many calories you should eat a day on average in order to achieve your weight loss goals.
For example, lets say that you wanted to lose 2lbs of fat a week. One pound of fat is equal to 3500 calories. Two pounds of fat would therefore be equal to 7000 calories. So if you ate 7000 calories less per week than your body needs to maintain (called a calorie deficit), then you will lose 2lbs a week.
Since there are 7 days a week, you can split that 7000 calorie deficit you need to create to lose 2lbs of fat into a 1000 calorie a day deficit.
Since your body's maintenance level is 3598 calories a day, if you reduced that by 1000 calories a day to 2598 calories, you should achieve your 2lb per week fat loss goal. At 1700 calories a day you will lose about 3.5-4lbs of fat a week.
Hope I didn't confuse you too bad.
