Alright, let's work through 20987371 times 98391215 step by step
20987371 × 98391215 = 98391215 × (20987371)
+ 98391215 × 1 that results in 98391215
+ 98391215 × 70 yielding 6887385050
+ 98391215 × 300 that equals 29517364500
+ 98391215 × 7000 that equals 688738505000
+ 98391215 × 80000 resulting in 7871297200000
+ 98391215 × 900000 that is equal 88552093500000
+ 98391215 × 0000000 what gives us 0
+ 98391215 × 20000000 resulting in 1967824300000000

= 2064972932345765
