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Owlet puzzle #8

Released Monday, July 13, 2026 UTC

The five clues

1. A four-digit number.
2. A perfect number.
3. The fourth one.
4. 8128 = 2⁶ · (2⁷−1) = 64 · 127.
5. Its divisor sum σ(n) equals 2n exactly.

Backstory

Fourth perfect number. After 8128, the next is 33,550,336.

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