Alright, let's work through 89407881 times 18162581 step by step
89407881 × 18162581 = 18162581 × (89407881)
+ 18162581 × 1 resulting in 18162581
+ 18162581 × 80 giving us 1453006480
+ 18162581 × 800 giving us 14530064800
+ 18162581 × 7000 producing 127138067000
+ 18162581 × 00000 what gives us 0
+ 18162581 × 400000 which equals 7265032400000
+ 18162581 × 9000000 giving us 163463229000000
+ 18162581 × 80000000 that equals 1453006480000000

= 1623877880700861
