Alright, let's work through 64836485 times 86142009 step by step
64836485 × 86142009 = 86142009 × (64836485)
+ 86142009 × 5 that results in 430710045
+ 86142009 × 80 that is equal 6891360720
+ 86142009 × 400 yielding 34456803600
+ 86142009 × 6000 what gives us 516852054000
+ 86142009 × 30000 what gives us 2584260270000
+ 86142009 × 800000 that equals 68913607200000
+ 86142009 × 4000000 what gives us 344568036000000
+ 86142009 × 60000000 that is equal 5168520540000000

= 5585145074398365
