A new riddle.
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A man walks into a nightclub where the bouncers test everybody before allowing entry. A woman walks to the bouncers & they say 6 to which the woman replies 3 & is granted entry. A short man walks to the bouncers say 12, to which he replies 6 & he enters the nightclub. The first guy thinks he has figured it out & approaches the bouncers & the bouncers say 4 to which he says 2, but they won't let him in. What should have he had said?