More plausible theory: 1 digit is to simple. 3 is too many. 2 is about right. Something non-prime of course, but with three prime factors. 42 is nice. Rolls of

More plausible theory: 1 digit is to simple. 3 is too many. 2 is about right. Something non-prime of course, but with three prime factors. 42 is nice. Rolls off the tongue, and ends in "ooo".