Alright, let's work through 6439 times 1724 step by step
6439 × 1724 = 1724 × (6439)
+ 1724 × 9 giving us 15516
+ 1724 × 30 that results in 51720
+ 1724 × 400 that results in 689600
+ 1724 × 6000 resulting in 10344000

= 11100836
