I would like to know which area of Mathematics would be most beneficial to cryptography. Surely Algebraic Number Theory and maybe to a lesser extend, Elliptic Curves, are closely linked to Cryptography; but are there more fields that would apply neatly to Cryptography?
What topics would you recommend to a Maths graduate who is looking for a career in Cryptography?
(I wanted to tag this as a "soft-question" as they do in math.stackexchange)