Alright, let's work through 85138589 times 81279463 step by step
85138589 × 81279463 = 81279463 × (85138589)
+ 81279463 × 9 giving us 731515167
+ 81279463 × 80 giving us 6502357040
+ 81279463 × 500 what gives us 40639731500
+ 81279463 × 8000 which equals 650235704000
+ 81279463 × 30000 resulting in 2438383890000
+ 81279463 × 100000 that is equal 8127946300000
+ 81279463 × 5000000 which equals 406397315000000
+ 81279463 × 80000000 giving us 6502357040000000

= 6920018794497707
