Alright, let's work through 19764455 times 78745640 step by step
19764455 × 78745640 = 78745640 × (19764455)
+ 78745640 × 5 producing 393728200
+ 78745640 × 50 which equals 3937282000
+ 78745640 × 400 that equals 31498256000
+ 78745640 × 4000 producing 314982560000
+ 78745640 × 60000 what gives us 4724738400000
+ 78745640 × 700000 what gives us 55121948000000
+ 78745640 × 9000000 resulting in 708710760000000
+ 78745640 × 10000000 producing 787456400000000

= 1556364658226200
