Alright, let's work through 3901 times 6307 step by step
3901 × 6307 = 6307 × (3901)
+ 6307 × 1 producing 6307
+ 6307 × 00 which equals 0
+ 6307 × 900 that is equal 5676300
+ 6307 × 3000 that is equal 18921000

= 24603607
