How do I convert an interval into a number of hours with postgres?

Say I have an interval like

4 days 10:00:00

in postgres. How do I convert that to a number of hours (106 in this case?) Is there a function or should I bite the bullet and do something like

extract(days, my_interval) * 24 + extract(hours, my_interval)

Probably the easiest way is:

SELECT EXTRACT(epoch FROM my_interval)/3600

If you want integer i.e. number of days:

SELECT (EXTRACT(epoch FROM (SELECT (NOW() - '2014-08-02 08:10:56')))/86400)::int