Aisha says every prime number is odd, so 2 cannot possibly be a prime number since it's even

Why

Aisha has noticed a real pattern — after 2, every prime number really is odd, and that pattern is strong enough to feel like a rule. The gap is treating "true for almost all of them" as "true for every single one," when one exception is enough to break a rule. A prime number is simply a number with exactly two factors — 1 and itself, nothing else. Check 2: its only factors are 1 and 2, so it qualifies as prime just like 3, 5, and 7 do. It happens to be even purely because it's the smallest prime and its own value is 2 — being even and being prime are two separate questions that just happen to overlap once. Try dividing any other even number by 2 — 4, 6, 8, 100 — and you'll always find a third factor, which is exactly why 2 is the ONLY even prime in existence. Vikram is right: 2 is prime, and it's worth remembering as the one exception that proves counting exceptions matters.