Math majors do much better on the LSAT (the standardized law school admissions test) than any other undergraduate major. Math majors also have the highest rate of admission to medical school and the best MCAT scores. Math majors tend to be among the most economically successful majors after graduation (second only to engineers). Math majors also do well on the GMATs (business school); not as well as some other quantitative discipline majors but better than either economics majors or undergraduate business majors.
Philosophy and physics majors also do well on standardized tests connected to further graduate study. Education majors tend to do worst on both the LSAT and the GRE (see also here).
Alas, math majors pay a price for their exceptional test scores: less sex.