Alright, let's work through 12694352 times 53640456 step by step
12694352 × 53640456 = 53640456 × (12694352)
+ 53640456 × 2 resulting in 107280912
+ 53640456 × 50 that equals 2682022800
+ 53640456 × 300 which equals 16092136800
+ 53640456 × 4000 that equals 214561824000
+ 53640456 × 90000 producing 4827641040000
+ 53640456 × 600000 that results in 32184273600000
+ 53640456 × 2000000 resulting in 107280912000000
+ 53640456 × 10000000 that is equal 536404560000000

= 680930829904512
