Surface Area—Displays the total surface area of all objects in the selection, in units squared.If surface area measures 46,980,499.99 How do I read the numbers?46million,980 thousand,499.What about two last digits after period?
In this case it would be 46 million 980 thousand 499 and 99/100. This is given in English units where the "," separates thousands and the "." is a decimal separator.
If you know the Units of the drawing (feet or inches or meters or millimeters, etc) you can go to the Markup & Measure tab and click the down arrow/triangle in the Measure panel and select 2D Units and Scale. There you can set the Drawing Units of your file and how you want to display them. You can also set the Precision to get rid of (or increase) the decimal precision. Unlike AutoCAD however, you cannot change the separators used. You're kind of stuck with what you see.
Hope this helps.