You can use a tool like VirusTotal to upload the file (or its MD5 hash). This will tell you if the file is known for containing malware or if it has been flagged in other databases.
Because the filename is generic—likely a system-generated string from a security camera, a messaging app (like WhatsApp or Telegram), or a private database—it could refer to several different things depending on the context in which you found it. Common Sources for This Type of Filename 39518.mp4
"39518.mp4" is not a widely recognized viral video, historical event, or standard technical file name that corresponds to a single, specific piece of media in the public domain. You can use a tool like VirusTotal to
Many NVR (Network Video Recorder) systems use numerical strings to timestamp or index clips. Common Sources for This Type of Filename "39518