7297
This number is a prime.
The diagonals of a regular 24-gon intersect at 7297
internal points (6144 intersections of two diagonals, 864
of three, 264 of four, 24 of five, and one intersection of
twelve diagonals). [Caldwell]
The smallest emirp that remains an emirp when each digit is
repeated a number of times equal to its complement:
777222222229777. [Beedassy]
(There is one curio for this number that has not yet been approved by an editor.)
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