Alright, let's work through 77681521 times 42912640 step by step
77681521 × 42912640 = 42912640 × (77681521)
+ 42912640 × 1 resulting in 42912640
+ 42912640 × 20 resulting in 858252800
+ 42912640 × 500 that is equal 21456320000
+ 42912640 × 1000 resulting in 42912640000
+ 42912640 × 80000 that is equal 3433011200000
+ 42912640 × 600000 that is equal 25747584000000
+ 42912640 × 7000000 yielding 300388480000000
+ 42912640 × 70000000 giving us 3003884800000000

= 3333519145325440
