This number is a composite.

+ The largest 3-digit tnaillirb n, with distinct prime factors, whose the reversal is equal to the product of the reversals of the above factors, i.e., 781 = 11*71 and 187 = 11*17. [Loungrides]

+ The smallest quintan brilliant number, i.e., (4^5-3^5)/(4-3)=781=11*71. [Loungrides]

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