Catalyzes the hydrolysis of the free cytosolic methylated adenosine nucleotide N(6)-methyl-AMP (N6-mAMP) to produce inositol monophosphate (IMP) and methylamine (PubMed:21755941, PubMed:29884623). Is required for the catabolism of cytosolic N6-mAMP, which is derived from the degradation of mRNA containing N6-methylated adenine (m6A) (PubMed:21755941, PubMed:29884623). Catalyzes the removal of different alkyl groups not only from N6-substituted purine or 2-aminopurine nucleoside monophosphates but also from O6-substituted compounds in vitro (PubMed:21755941). H(+) + H2O + N(6)-methyl-AMP = IMP + methylamine Binds 1 zinc ion per subunit. Monomer. Belongs to the metallo-dependent hydrolases superfamily. Adenosine and AMP deaminases family.