Owlet puzzle #21
Released Sunday, July 26, 2026 UTC
168
the answer for puzzle #21
The five clues
- A three-digit multiple of twenty-four.
- It has sixteen divisors — a lot for its size.
- The order of the second-smallest nonabelian simple group.
- PSL(2,7) has order 168.
- Also equals π(1000) — the count of primes below one thousand.
Backstory
168 = |PSL(2,7)| = |PSL(3,2)| is the order of the smallest nonabelian simple group after A₅, and equals the automorphism group of the Fano plane. It also happens to equal both π(1000) = 168 primes under one thousand and 168 hours in a week — an unrelated numerical coincidence.
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