Alright, let's work through 87203989 times 54953207 step by step
87203989 × 54953207 = 54953207 × (87203989)
+ 54953207 × 9 which equals 494578863
+ 54953207 × 80 that is equal 4396256560
+ 54953207 × 900 which equals 49457886300
+ 54953207 × 3000 yielding 164859621000
+ 54953207 × 00000 producing 0
+ 54953207 × 200000 producing 10990641400000
+ 54953207 × 7000000 which equals 384672449000000
+ 54953207 × 80000000 which equals 4396256560000000

= 4792138858742723
