180689
This number is a composite.
The smallest invertible prime containing all of the
invertible digits that represents the hypotenuse of a
Pythagorean triangle {6800,180561,180689}. Curiously, it
represents the hypotenuse of three more Pythagorean
triples: {35780, 177111, 180689}; {42420, 175639, 180689};
{76360, 163761, 180689}. [Bajpai]
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