Alright, let's work through 90279402 times 71256977 step by step
90279402 × 71256977 = 71256977 × (90279402)
+ 71256977 × 2 yielding 142513954
+ 71256977 × 00 that results in 0
+ 71256977 × 400 that results in 28502790800
+ 71256977 × 9000 what gives us 641312793000
+ 71256977 × 70000 which equals 4987988390000
+ 71256977 × 200000 producing 14251395400000
+ 71256977 × 0000000 producing 0
+ 71256977 × 90000000 that results in 6413127930000000

= 6433037271887754
