Alright, let's work through 87856117 times 7709558 step by step
87856117 × 7709558 = 7709558 × (87856117)
+ 7709558 × 7 which equals 53966906
+ 7709558 × 10 yielding 77095580
+ 7709558 × 100 giving us 770955800
+ 7709558 × 6000 resulting in 46257348000
+ 7709558 × 50000 that results in 385477900000
+ 7709558 × 800000 which equals 6167646400000
+ 7709558 × 7000000 producing 53966906000000
+ 7709558 × 80000000 producing 616764640000000

= 677331829666286
