Parallel
Genesis 5:31
Rahlfs Septuagint (1935) · Berean Standard Bible
καὶ ἐγένοντο πᾶσαι αἱ ἡμέραι Λαμεχ ἑπτακόσια καὶ πεντήκοντα τρία ἔτη καὶ ἀπέθανεν
So Lamech lived a total of 777 years, and then he died.