How Good is Pure Math at Brown?

I still have a little while until I have to apply to colleges but so far Brown seems to offer a lot of what I’m looking for.

As of now, I’m mostly interested in pure math, specifically cryptography (I’m more interested in the theoretical side than the applied, which is based primarily in number theory among other fields of pure math) if that makes any difference, however I’ve seen reviews of the pure math department that range from horrendous to pretty good.

I know it isn’t as strong as the applied math and CS departments, but could some Brown students who have taken pure math courses give me some insight on what their experiences with the pure math department have been? By the time I graduate high school I will have done Calc 3, Linear Algebra, and an intro to number theory if that’s relevant.