Alright, let's work through 2639 times 9660 step by step
2639 × 9660 = 9660 × (2639)
+ 9660 × 9 that results in 86940
+ 9660 × 30 giving us 289800
+ 9660 × 600 that results in 5796000
+ 9660 × 2000 resulting in 19320000

= 25492740
