Alright, let's work through 12668421 times 12349909 step by step
12668421 × 12349909 = 12349909 × (12668421)
+ 12349909 × 1 producing 12349909
+ 12349909 × 20 that equals 246998180
+ 12349909 × 400 yielding 4939963600
+ 12349909 × 8000 giving us 98799272000
+ 12349909 × 60000 yielding 740994540000
+ 12349909 × 600000 producing 7409945400000
+ 12349909 × 2000000 producing 24699818000000
+ 12349909 × 10000000 giving us 123499090000000

= 156453846523689
