The '12' is the equivalent of a copyright stamp, although in this example it also has a paper stamp applied too. The number equated to a list of mechanical copyright holders of the music. I don't think anyone has yet bothered to work out the sequence.
The '11834' is the transfer serial number for the 29cm disc, that is when a disc 'master' was made via a pantograph transfer from which stampers could be produced. The 24cm issue of the disc had the number '4822'