Number:0 (Meta, no ontology)

From Compile Worlds

Zero is a number before one and after negative one. Dividing anything by zero causes black holes to spontaneously appear somewhere in the world, therefore most processors have safeguards against attempting the operations. Legacy calculators however might still divide by zero; it's recommended you dispose of them properly.

It's rumored that dividing by zero also causes kittens to spontaneously die, which is yet another reason to never attempt this dangerous feat.