221

This number is a composite.

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The smallest squarefree brilliant number that represents the hypotenuse of four Pythagoren triangles, i.e., (21^2+220^2=221^2), (85^2+204^2=221^2), (104^2+195^2=221^2), (140^2+171^2=221^2). Curiously, 221 is also expressible as the sum of two squares in two different ways: (5^2+14^2 = 221 = 10^2+11^2). [Bajpai]