The composite cofactor of L1201 was the product of 81-digit and 138-digit prime numbers:

81-digit prime factor:
145543841206506434178337270947917411039678170392804973454846367934327209589727911

138-digit prime factor:
164848054536016316819264243938411057683177243483901879022001464730610024509823614031133225605993769608060150120565293983090482323236609041

Thanks to Carlos Pinho from SETI.USA team for performing the postprocessing. The factors have been reported to the Fibonacci project.