356
This number is a composite.
The 356th prime is 2393. Note that 3562393 is prime. Furthermore, 356 + 2393 = 2749 is prime and 3 + 5 + 6 + 2 + 3 + 9 + 3 = 31 is too. [Homewood]
(There is one curio for this number that has not yet been approved by an editor.)
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