How to know oracle client bit version in linux whether 32 bit or 64 bit

How to know oracle client bit version in linux?

*For this you need oracle user

$ cd $ORACLE_HOME/bin

$ file sqlplus

sqlplus: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.18, not stripped