No problem, we've got 3998 and 7740 to multiply
3998 × 7740 = 7740 × (3998)
+ 7740 × 8 that is equal 61920
+ 7740 × 90 resulting in 696600
+ 7740 × 900 yielding 6966000
+ 7740 × 3000 yielding 23220000

= 30944520
