Alright, let's work through 87170277 times 78301247 step by step
87170277 × 78301247 = 78301247 × (87170277)
+ 78301247 × 7 resulting in 548108729
+ 78301247 × 70 resulting in 5481087290
+ 78301247 × 200 resulting in 15660249400
+ 78301247 × 0000 which equals 0
+ 78301247 × 70000 what gives us 5481087290000
+ 78301247 × 100000 which equals 7830124700000
+ 78301247 × 7000000 that equals 548108729000000
+ 78301247 × 80000000 resulting in 6264099760000000

= 6825541390435419
