Modular arithmetic help for the upcoming test

My professor just dropped a massive modular arithmetic test on us, and I am totally lost right now. I keep getting tripped up on the congruences and those huge exponents when I try to solve things manually. I really need a reliable service or some interactive tool that can handle the calculations and help me check my work before I turn it in. What do you guys use when you are stuck on this kind of math?

Math classes always seem to ramp up the difficulty right when the midterms are around the corner. It is way too easy to make a small mistake with the remainders that throws off the entire problem. You could check out WolframAlpha since it handles those modular equations pretty well. Symbolab is also a good pick for seeing a bit more of the logic behind the steps.

Staying on top of these assignments is a lot easier when you have a way to verify the numbers quickly. Trying to figure out complex modular inverses by hand usually leads to some pretty annoying errors. You can find interactive modular arithmetic tools here: https://miketatemath.org/ . These tools make it simple to check calculations and work through modular equations without all the manual grunt work. It is pretty useful for checking congruences, inverses, and modular exponent stuff without doing every calculation by hand.