This number is a composite.

+ The largest perfect number whose index is equal to the number of digits. [Pol]

+ The largest perfect number of the form 2^(p-1)*(2^p-1), where the prime number p and the perfect number both have the same index. [Pol]

+ In addition to being a perfect number, its reverse (8218) is the 8128th positive integer that is non-square. [Gaydos]

(There is one curio for this number that has not yet been approved by an editor.)

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