Alright, let's work through 89239980 times 9919912 step by step
89239980 × 9919912 = 9919912 × (89239980)
+ 9919912 × 0 what gives us 0
+ 9919912 × 80 that equals 793592960
+ 9919912 × 900 yielding 8927920800
+ 9919912 × 9000 that is equal 89279208000
+ 9919912 × 30000 that results in 297597360000
+ 9919912 × 200000 yielding 1983982400000
+ 9919912 × 9000000 which equals 89279208000000
+ 9919912 × 80000000 resulting in 793592960000000

= 885252748481760
