no, you are wrong. Last number on the tire is the Metal Rim Diameter. First number is width, 2nd number is how tall is the rubber part.
If you are trying to make the tire bigger in Diameter, you go with 235/70/R16. If you want it wider, you go 245/65/R16. You can NOT mount a 17 inch tire on a 16 inch rim, it just doesn't fit physically. You have to buy the whole Wheel, not just the tire.