Q:

Remove specific file if it hasn't been modified for 1 day

I want to delete the specific file, std_info under /tmp, 
if it hasn't been modified within a day (or 1440 minutes).
For now, I created the following syntax that prints only the files that were modified within one day:
 find /tmp -mmin -1440 -type f -exec ls -l {} +

but how to do the opposite way? 
In order to  removed the std_info file under /tmp that wasn't modified within 1 day?

A:

find /tmp/std_info -mmin +1440 -delete

Assuming that /tmp/std_info is a file, this would examine that file, and if it was modified more than 1440 minutes ago it would be deleted.  Use -exec rm {} \; in place of -delete if your find does not have -delete.
If the file might not exist, use
[ -e /tmp/std_info ] && find /tmp/std_info -mmin +1440 -delete

To delete any file named std_info under /tmp that was modified more than 1440 minutes ago, use
find /tmp ! -type d -name std_info -mmin +1440 -delete

I'm using ! -type d to also include symbolic links and other type of files other than directories.

