The number has no special significance to me, but 022333 has enough digits to be a six-pin bitting, so perhaps it is the bitting. "0" usually denotes no cut at all, but it sometimes denotes the deepest cut. The rest of the cuts are numbered by depth, "1" being the shallowest and "9" the deepest. If you look at the depths of cuts on your key, you may be able to see whether the depths correspond to the numbers.
If there is a manufacturer's name on your lock, it may be stamped on the plate where the latch sticks out. If you have an old mortise lock, the manufacturer's name may be embossed on the case cover.