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

81-digit prime factor:
14554384120650643417833727094791741103967817039280 4973454846367934327209589727911

138-digit prime factor:
16484805453601631681926424393841105768317724348390 18790220014647306100245098236140311332256059937696 08060150120565293983090482323236609041

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