Alright, let's work through 1591 times 1023 step by step
1591 × 1023 = 1023 × (1591)
+ 1023 × 1 that results in 1023
+ 1023 × 90 yielding 92070
+ 1023 × 500 that is equal 511500
+ 1023 × 1000 that equals 1023000

= 1627593
