This was ~10 years ago. 3-digit numbers were all gone. Having a million 6 digit numbers increases chances to actually get one by registering an expired domain/e

This was ~10 years ago. 3-digit numbers were all gone. Having a million 6 digit numbers increases chances to actually get one by registering an expired domain/email address. In times of 9 digit numbers, 6 digit numbers were still sufficiently unique :)