Possible Clues:

• Three, 13 and 21
• 69 and 101, but not 86
• Figures on right-hand pages, or an apt title for this puzzle
• *Prius, for the most part
• All but one prime
• 2019 and 2021, e.g
• They're not even in the Bible after all, which is peculiar in 9 across
• They're not even occasional painkillers!
• 1, 3, 5, 7, etc
• Half of 8 across plus 250, for instance = 13,579, for example?