Alright, let's work through 5902 times 7821 step by step
5902 × 7821 = 7821 × (5902)
+ 7821 × 2 that is equal 15642
+ 7821 × 00 yielding 0
+ 7821 × 900 yielding 7038900
+ 7821 × 5000 yielding 39105000

= 46159542
