Alright, let's work through 1290 times 9658 step by step
1290 × 9658 = 9658 × (1290)
+ 9658 × 0 that equals 0
+ 9658 × 90 that equals 869220
+ 9658 × 200 resulting in 1931600
+ 9658 × 1000 that is equal 9658000

= 12458820
