If you look at the doc string of kbd (C-h f kbd)), it mentions that there is an approximate inverse function called key-description. If you apply this function to the vector, you get
(key-description [27 213909545])
Note the different order!
The explanation is that these represent modifier keys: that's ESC followed by the key ...
C-h b lists all the keybindings currently in effect, and groups them by mode.
Similarly, C-h m displays a short description of the current major mode, and all active minor modes. This includes the keys bound to the maps for each mode. It doesn't include keys bound in the global keymap, so if you don't find your key here, that might be why.
The output from ...