How to check if my software is 32-bit or 64-bit

You can use the file command to check out what format has that executable. For example:

file /usr/bin/gedit
/usr/bin/gedit: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.24, BuildID[sha1]=0x5a388215eb6f60b420fc3b6d68ec52d563071f84, stripped

This simple command will show you whether the executable file is 32 bit(i386) or 64 bit(amd64) .

Syntax:

apt-cache show $(dpkg -S /path/to/the/file | awk -F ':' '{print $1 }') | awk '/Architecture:/ {print $2}' -

Example:

$ apt-cache show $(dpkg -S /usr/bin/gedit | awk -F ':' '{print $1 }') | awk '/Architecture:/ {print $2}' -
amd64

Explanation:

dpkg -S command grabs the package in which the file actually belongs to.apt-cache show package command will shows the details about the package.From that details, awk grabs only the Architecture part and redirects it to stdout.

OR

You can try this command also,

$ dpkg -l $(dpkg -S /usr/bin/gedit | awk -F ':' '{print $1 }') | awk '/ii/ {print $4}'
amd64