Okay, so I've been running the numbers, and here's what I have:
If I go Warlock 4, Sorcerer 4, Fighter 3 (Eldritch Knight), Rogue 3 (Arcane Trickster), Wizard 2 (Illusionist), Cleric 1, Druid 2, and bard 1, as well as starting out as a tiefling, I can net 32 cantrips. Those numbers are...