Alright, let's work through 77700871 times 80728050 step by step
77700871 × 80728050 = 80728050 × (77700871)
+ 80728050 × 1 that is equal 80728050
+ 80728050 × 70 giving us 5650963500
+ 80728050 × 800 which equals 64582440000
+ 80728050 × 0000 that equals 0
+ 80728050 × 00000 that results in 0
+ 80728050 × 700000 yielding 56509635000000
+ 80728050 × 7000000 that is equal 565096350000000
+ 80728050 × 70000000 that is equal 5650963500000000

= 6272639799131550
