Alright, let's work through 86873712 times 44634712 step by step
86873712 × 44634712 = 44634712 × (86873712)
+ 44634712 × 2 that equals 89269424
+ 44634712 × 10 that results in 446347120
+ 44634712 × 700 that is equal 31244298400
+ 44634712 × 3000 which equals 133904136000
+ 44634712 × 70000 producing 3124429840000
+ 44634712 × 800000 that equals 35707769600000
+ 44634712 × 6000000 resulting in 267808272000000
+ 44634712 × 80000000 giving us 3570776960000000

= 3877583115490944
