Is your Linux 64-bit?

Two easy ways to check it:

[root@swdartifact01 ~]# uname -m
x86_64

and

[root@swdartifact01 ~]# file /usr/bin/file
/usr/bin/file: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.18, stripped

First one, is the name of the kernel. Second one is binary file on the system, which tells that the system is most likely 64-bit system.