Alright, let's work through 90618009 times 51578547 step by step
90618009 × 51578547 = 51578547 × (90618009)
+ 51578547 × 9 giving us 464206923
+ 51578547 × 00 that is equal 0
+ 51578547 × 000 producing 0
+ 51578547 × 8000 resulting in 412628376000
+ 51578547 × 10000 giving us 515785470000
+ 51578547 × 600000 what gives us 30947128200000
+ 51578547 × 0000000 giving us 0
+ 51578547 × 90000000 that results in 4642069230000000

= 4673945236252923
