Thank you for such a great work and especially for making it available for free! For anyone interested, I can also recommend trying out Sage! There is also this

Thank you for such a great work and especially for making it available for free! For anyone interested, I can also recommend trying out Sage! There is also this free book (http://abstract.pugetsound.edu/sage-aata.html http://abstract.pugetsound.edu/sage-aata.html) on Abstract Algebra which includes Sage exercises. The most prominent application of number theory in computer science is probably cryptography. I can highly recommend "An Introduction to Mathematical Cryptography" by Hoffstein, Pipher and Silverman in that area.