No problem, we've got 6480 and 216 to multiply
6480 × 216 = 216 × (6480)
+ 216 × 0 yielding 0
+ 216 × 80 that results in 17280
+ 216 × 400 that is equal 86400
+ 216 × 6000 giving us 1296000

= 1399680
