Evaluation of run time in QUEUEDJOB table

For use within SQL queries, how do folks evaluate the total run time of jobs in the QUEUEDJOB table, since the STARTTIME & STOPTIME fields are formatted as (decimal(6,0),not null), instead of date/time format?

We are trying to write a query to identify "long-running" jobs, in the active job queue by comparing the STARTTIME to GETDATE() tme stamp, but not sure how to convert the STARTDATE formatting in order to be able to successfully compare the two.

Any advice would be appreciated. Thank you in advance.