Alright, let's work through 3580 times 729 step by step
3580 × 729 = 729 × (3580)
+ 729 × 0 which equals 0
+ 729 × 80 that results in 58320
+ 729 × 500 that equals 364500
+ 729 × 3000 that results in 2187000

= 2609820
