1-digit prime factors: 3

2-digit prime factors: 3

3-digit prime factors: 5

4-digit prime factors: 14

5-digit prime factors: 32

6-digit prime factors: 74

7-digit prime factors: 151

8-digit prime factors: 356

9-digit prime factors: 707

10-digit prime factors: 1400

11-digit prime factors: 2811

12-digit prime factors: 5397

13-digit prime factors: 10568

Number of known prime numbers: 21521 (258021 digits)

Perl script written by Dario Alejandro Alpern. Last updated on May 25th, 2015.