Alright, let's work through 85084521 times 89806361 step by step
85084521 × 89806361 = 89806361 × (85084521)
+ 89806361 × 1 resulting in 89806361
+ 89806361 × 20 giving us 1796127220
+ 89806361 × 500 producing 44903180500
+ 89806361 × 4000 resulting in 359225444000
+ 89806361 × 80000 yielding 7184508880000
+ 89806361 × 000000 resulting in 0
+ 89806361 × 5000000 that equals 449031805000000
+ 89806361 × 80000000 producing 7184508880000000

= 7641131208438081
