Is a masters in applied math/statistics where I learn machine learning a good way to get a job doing big data analysis or do I need to major in CS?

My undergraduate major was in math and I've been an actuary for two years, but find it boring. If I were to go to an applied math or statistics graduate program and take machine learning, data mining, neural computing, and the cs prerequisites necessary (there's about 5 courses including java and intro to ai) for those classes, would that be a good background for a career in machine learning and data mining or do you need a more extensive background in cs? Are there certain types of jobs specifically for more mathematical/statistical people? Finally, is there anyone here who does predictive modeling or catastrophe risk modeling using machine learning and data mining? A career in that would mean I didn't waste these first five actuarial exams.