: Use a standard media player like VLC Media Player to see if the file is a valid video.
: The .mp4 extension (MPEG-4 Part 14) is a digital multimedia container format most commonly used to store video and audio. It is a universal standard compatible with almost all modern devices, from smartphones to smart TVs. 36236mp4
Since informative text must be based on facts and clear details, I've drafted a guide on how to handle this type of digital file. Understanding the 36236.mp4 File : Use a standard media player like VLC