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487² divides 10⁴⁸⁶ - 1.

487 is the smallest prime p such that p and p³ have the same sum of digits. [Honaker]

There are 487 Hadamard matrices of order 28. Note that 28 is a perfect number. [Rupinski]

487 = (4!₂ + 8!₂ + 7!₂) - ((4) + (8) + (7)). Note that 487 is the smallest prime with this property. [Firoozbakht]

Fermat claimed (correctly) that a number is the sum of three squares unless it is of the form 4ⁿ(8m + 7), with n,m greater than or equal to 0.