Alright, let's work through 83943580 times 18338538 step by step
83943580 × 18338538 = 18338538 × (83943580)
+ 18338538 × 0 that results in 0
+ 18338538 × 80 that is equal 1467083040
+ 18338538 × 500 that results in 9169269000
+ 18338538 × 3000 producing 55015614000
+ 18338538 × 40000 producing 733541520000
+ 18338538 × 900000 what gives us 16504684200000
+ 18338538 × 3000000 that is equal 55015614000000
+ 18338538 × 80000000 yielding 1467083040000000

= 1539402531686040
