I am currently a pure math major, but my advisor told me that I should consider switching my major to financial math. The reason he said this is because I am interested in actuary work and he said it might be a better major for the type of career I want to pursue. However, I personally do not want to switch my major. The reason is because I am interested in taking some of the more theoretical math classes, and I would not get to take any of those if I switched to financial math.
It may be that either pure math or financial math majors have enough free electives that you can use those electives to cover the other area. E.g. major in pure math while taking the actuarial-prep courses in your free electives, or major in financial math and take the pure math courses in your free electives.
However, since you did not name your college, others cannot help you determine whether doing this is easy or difficult.