ELI5: Explain Like I'm 5

Number theory

Number theory is about numbers and how they work. It's like a special way to look at math. Numbers are like building blocks, and when you know how to use them, you can build lots of things. In number theory, mathematicians look for patterns and relationships between numbers. For example, they look at the different ways numbers can be divided, multiplied and combined to come up with new numbers.
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