The largest cube that fits in a corner of a 20×16×12 cm cuboid has side = min(20, 16, 12) = 12 cm.

Volume of cuboid = 20 × 16 × 12 = 3,840 cm³
Volume of carved cube = 12³ = 1,728 cm³

Remaining volume = 3,840 − 1,728 = 2,112 cm³

Final Answer: 2,112 cm³