1666375426964.mp4

: Use Handbrake if the file is too large to share.

: Use a file explorer to search your entire drive/phone for that specific string of numbers. 5. Managing and Converting 1666375426964.mp4

: A popular command-line tool for fixing MP4s that "won't open" because the recording was cut off. : Use Handbrake if the file is too large to share

: The number 1666375426964 is a Unix timestamp in milliseconds. It translates to Friday, October 21, 2022, at 3:23:46 PM (GMT) . a game recording

Could you tell me or where you found the filename ? I can give you a much more specific guide if I know if it's a security camera clip, a game recording, or a personal memo.