Well OK, I was mistaken there, the sensor is IMX300 which really is physically 5520x4140 pixel array which makes it 22,8Mpix totals.

The other thing again is whether such a device makes sense as an image sensor since the surface area is so puny 6,05mm*5,03mm.
If you assume the whole surface is crammed edge-to-edge so full of pixels you can stuff 'em, the pixel size is 1,09um*1,21um, which makes a pixel area of 1,33um2 which so tiny it is absolutely no use to anybody seriously contemplating photography.
Add to that the miniature optics that the light has to pass through to the sensor any you see the whole thing just cannot work due to laws of physics.

In my Canon DSLR dating from the last decade the pixel area is 55um2 which is more than 40 times larger than on the IMX300.

There are fundamental physics laws in play here, you cannot get around those by having better materials and manufacturing.
Due to the properties of reality you just cannot cram more than a certain number of photons in a certain sized pixel in given time, the wave function just doesn't fold that way.