Alright, let's work through 99605809 times 21088301 step by step
99605809 × 21088301 = 21088301 × (99605809)
+ 21088301 × 9 producing 189794709
+ 21088301 × 00 yielding 0
+ 21088301 × 800 that is equal 16870640800
+ 21088301 × 5000 resulting in 105441505000
+ 21088301 × 00000 that is equal 0
+ 21088301 × 600000 that equals 12652980600000
+ 21088301 × 9000000 that equals 189794709000000
+ 21088301 × 90000000 which equals 1897947090000000

= 2100517281540509
