Replacing Numeric Column Blank Data With 0

PFB the screen shots of a table column data. I want to replace the blank column into zero so how can I do this?
Numeric Column

Hi @Biswajit_1993

May be you should try something like this, let me know

ifelse(isNotNull({Total Time in…}), {Total Time in…}, 0)

It showing syntax of the calculated field is incorrect.
Error Message

@Biswajit_1993 you have two curly in the calculation, look at the marked place