Let's calculate 2621 x 3980
2621 × 3980 = 3980 × (2621)
+ 3980 × 1 that results in 3980
+ 3980 × 20 resulting in 79600
+ 3980 × 600 that is equal 2388000
+ 3980 × 2000 that results in 7960000

= 10431580
