It belongs to the same genre as Smile.jpg or The Ring , where the horror stems from the idea of "viral" media that affects the physical world.
A rhythmic, metallic scratching sound grows louder, eventually revealed to be the sound of someone carving numbers into a wooden floor. 24644mp4
After the video ends, the file deletes itself, but not before corrupting every other image file on the user's computer, replacing them with a single frame from the video. It belongs to the same genre as Smile
In the mythos, 24644.mp4 is more than just a scary movie; it is described as a "sentient" file: metallic scratching sound grows louder