Alright, let's work through 54294879 times 80643968 step by step
54294879 × 80643968 = 80643968 × (54294879)
+ 80643968 × 9 what gives us 725795712
+ 80643968 × 70 yielding 5645077760
+ 80643968 × 800 yielding 64515174400
+ 80643968 × 4000 which equals 322575872000
+ 80643968 × 90000 that is equal 7257957120000
+ 80643968 × 200000 giving us 16128793600000
+ 80643968 × 4000000 yielding 322575872000000
+ 80643968 × 50000000 that results in 4032198400000000

= 4378554484639872
