Alright, let's work through 21512748 times 27073451 step by step
21512748 × 27073451 = 27073451 × (21512748)
+ 27073451 × 8 giving us 216587608
+ 27073451 × 40 giving us 1082938040
+ 27073451 × 700 that is equal 18951415700
+ 27073451 × 2000 that equals 54146902000
+ 27073451 × 10000 which equals 270734510000
+ 27073451 × 500000 producing 13536725500000
+ 27073451 × 1000000 what gives us 27073451000000
+ 27073451 × 20000000 yielding 541469020000000

= 582424328853348
