Alright, let's work through 1721 times 1392 step by step
1721 × 1392 = 1392 × (1721)
+ 1392 × 1 that equals 1392
+ 1392 × 20 yielding 27840
+ 1392 × 700 producing 974400
+ 1392 × 1000 giving us 1392000

= 2395632
