Catalyzes the hydrolysis of various purine and pyrimidine 5'-nucleotides, showing preference for 5'-nucleoside monophosphates and exhibiting the highest catalytic activity toward 5'-XMP. Shows also a relatively high phosphohydrolase activity toward the nucleotide precursors ribose-5-phosphate (R5P) and 5-phosphoribosyl-1-pyrophosphate (PRPP), and toward the non-natural substrate p-nitrophenyl phosphate (pNPP)