Changes In Personnel Number

Dear Experts,

I have uploaded data for 3495 employees in the production system with personnel number ranging from 1 to 00999999. and have also taken a actual run.

Now client is not keen to keep the personnel numbers as 1,2,3,4,5,etc, rather they want them to be replaced by the personnel number in the format as 100001, 100002, 100003, 100004 etc.

Request you to suggest me the way to implement the same.

Regards

SBC