Alright, let's work through 72790691 times 71873139 step by step
72790691 × 71873139 = 71873139 × (72790691)
+ 71873139 × 1 that results in 71873139
+ 71873139 × 90 that is equal 6468582510
+ 71873139 × 600 yielding 43123883400
+ 71873139 × 0000 what gives us 0
+ 71873139 × 90000 what gives us 6468582510000
+ 71873139 × 700000 which equals 50311197300000
+ 71873139 × 2000000 that equals 143746278000000
+ 71873139 × 70000000 yielding 5031119730000000

= 5231695452149049
