Ben Brantley of "The New York Times" described "A Number" as "stunning" and "a gripping dramatic consideration of what happens to autonomous identity in a world where people can be cloned". James M. Brandon had mixed sentiments in "Theatre Journal", arguing that while it "is a wellwritten play—evocative, disturbing, and with more than one surprise—it remains a troubled one that seems, in production, unfinished. " The critic disputed comparisons of the broken dialogue to that of David Mamet and said that "the language here is not nearly as compelling on the stage". However, Brandon praised the final scene as "brilliant" and said that one of its characters "serves as a welcome reminder that it is possible to have an ostensibly normal life", ultimately describing "A Number" as "one of the more intellectually vital scripts to emerge in the new century" despite shortcomings.