Catalysis of the reaction: 5-diphospho-1D-myo-inositol 1,3,4,6-tetrakisphosphate + H2O = 1D-myo-inositol 1,3,4,5,6-pentakisphosphate + H+ + phosphate.
5-diphosphoinositol 1,3,4,6-tetrakisphosphate diphosphatase activity