Alright, let's work through 521873 times 85699886 step by step
521873 × 85699886 = 85699886 × (521873)
+ 85699886 × 3 resulting in 257099658
+ 85699886 × 70 producing 5998992020
+ 85699886 × 800 which equals 68559908800
+ 85699886 × 1000 that equals 85699886000
+ 85699886 × 20000 yielding 1713997720000
+ 85699886 × 500000 that results in 42849943000000

= 44724456606478
