Definition of "numerological"

If you can't make up your mind whether to choose astrological, numerological, or some other type of spiritual guidance, don't worry.

1988 January 29, Achy Obejas, “Calendar”, in Chicago Reader‎

[Isaac Newton] was obsessed with alchemy. He spent hours copying alchemical recipes and trying to replicate them in his laboratory. He believed that the Bible contained numerological codes.

2014 June 21, “Magician’s brain”, in The Economist, volume 411, number 8892