Why do you need to convert COLUMNS_UPDATED() to @realUpdate?

What's wrong with it as it is?

And there is an easier way to do this conversion:

SET @realUpdate = CONVERT(int, COLUMNS_UPDATED() )

But you need to be sure you have less then 32 columns in the table, otherwise it will overflow int value.

But main point remains the same: what do you need it for?

There must be an easier way.