Formula in flaot field

I have a float field and need the data to present itself as a datetime. I have been unsuccessful at converting the entire field to datetime so I thought I would try a formula but have had no success. Can this be done?

I have data like so:

100599
10699
120597
etc...

and need to hit them as though they were datetime for order by and such...

or an 'in query' conversion...

ThanksI came up with a solution, thanks anyway.sql