Alright, let's work through 87089467 times 21079743 step by step
87089467 × 21079743 = 21079743 × (87089467)
+ 21079743 × 7 which equals 147558201
+ 21079743 × 60 producing 1264784580
+ 21079743 × 400 that equals 8431897200
+ 21079743 × 9000 what gives us 189717687000
+ 21079743 × 80000 that equals 1686379440000
+ 21079743 × 000000 what gives us 0
+ 21079743 × 7000000 that equals 147558201000000
+ 21079743 × 80000000 which equals 1686379440000000

= 1835823582366981
