The .rar extension indicates a compressed folder. The part19 means this is the 19th segment of a larger set. You usually need all parts (part1, part2, etc.) in the same folder to successfully extract the contents.
This filename format is very typical of large archives (like a long audiobook, a high-quality music collection, or a software package) that have been split into multiple smaller pieces for easier uploading and downloading. What this file usually represents: Download MP3 001 part19 rar
If you give me more context, I can help you find a safer or more direct way to listen to it! a high-quality music collection