Nucleotidase with a broad substrate specificity as it can dephosphorylate various ribo- and deoxyribonucleoside 5'-monophosphates and ribonucleoside 3'-monophosphates with highest affinity to 3'-AMP (PubMed:15489502). Also hydrolyzes polyphosphate (exopolyphosphatase activity) with the preference for short-chain-length substrates (P20-25) (PubMed:15489502). Might be involved in the regulation of dNTP and NTP pools, and in the turnover of 3'-mononucleotides produced by numerous intracellular RNases (T1, T2, and F) during the degradation of various RNAs (PubMed:15489502). Also plays a significant physiological role in stress-response and is required for the survival of E.coli in stationary growth phase (PubMed:15489502). a ribonucleoside 5'-phosphate + H2O = a ribonucleoside + phosphate a ribonucleoside 3'-phosphate + H2O = a ribonucleoside + phosphate [phosphate](n) + H2O = [phosphate](n-1) + H(+) + phosphate AMP + H2O = adenosine + phosphate GMP + H2O = guanosine + phosphate dGMP + H2O = 2'-deoxyguanosine + phosphate 3'-AMP + H2O = adenosine + phosphate 3'-CMP + H2O = cytidine + phosphate Binds 1 divalent metal cation per subunit. Highest nucleotidase activity with Mn(2+), followed by Co(2+), Ni(2+) and Mg(2+). Highest exopolyphosphatase activity with Mg(2+), followed by Co(2+) and Zn(2+). Inhibited by various ribo- or deoxyribonucleoside 5'-triphosphates but is insensitive to nucleoside diphosphates. Optimum pH is 7.0-7.2 for nucleotidase activity. Monomer and homooligomer in solution. The oligomeric complex consists of at least four subunits. Belongs to the SurE nucleotidase family. Was originally annotated as an acid phosphatase (EC 3.1.3.2).