seeing /printing values above the limit

Hi , I am doing arithmetic operations using fixed-point toolbox and the resulting numbers are more than 2^53-1(sometimes they are in the order of 2^70 or sth).But MATLAB is not showing it .for e.g if my result is (2^66-1) .MATLAB shows it as 7.378697629483821e+019..I really need to see the numbers .Please tell me a method to display the number .Also If I want to print it to a file what format should I use ?