Can anyone recommend me a textbook for Number Theory (Undergraduate)?

[Math100]

So far, I've taken Ordinary Differential Equations and Introduction to Mathematical Proof. My plan is to take "Introduction To Number Theory" for next semester in Spring 2022. But my professor told me that she won't use a textbook for this class. I was wondering what are some of the good textbook(s) choices for Introductory (Elementary) Number Theory, that are suitable for undergraduate students like me. I want a textbook that has many practice problems and accurate answers. If anyone has any resources or know the textbooks, then please tell me the title of the textbook, edition, author, etc. Thank you.

 

[O2PiArr]

Oystein Ore's "Number Theory and it's History" might be a good place to start. He does cover a fair amount of mathematics as well as the history. ETA- it's only algebra, so shouldn't present a problem. Well, it does have some trig in it, but if you're past ODE, you're good to go.

 

[MidgetDwarf]

Theres a really simple one, but it is written extremely well. Pommerhseim: A Lively Introduction To The Theory Of Numbers. A great way to practice proof writing, while learning some interesting math.

It is a gentle book, explanations are thorough, and easy to follow. However, another book will be needed after it...

 

[Math100]

Thank you, guys!