RPM Question, confusion on x86_64 packages and naming convention

This is probably a dumb question, however I can't find an answer via Google and it just isn't clear to me.

I'm installing Oracle on RHEL x86_64 and part of the requirements is to have unixODBC installed.

I did a dry run earlier this year and have a directory of all of the rpms that I needed to install before I could install Oracle.

I had alot of issues with unixODBC and had to put a ticket in with RH Support, however I realized the following:

There are two types that I noticed:

unixODBC64-2.2.14-3.el5.x86_64.rpm
unixODBC64-devel-2.2.14-3.el5.e86_64.rpm
unixODBC64-libs-2.2.14-3.el5.x86_64.rpm

and

unixODBC-2.2.11-10.el5.x86_64.rpm
unixODBC-devel-2.2.11-10.el5.x86_64.rpm
unixODBC-libs-2.2.11-10.el5.x86_64.rpm

One has 64 in the name (unixODBC64) and the latter has 64 to file name to show that it is a x86_64.

If I tried to use rpm -ivh on any of the unixODBC64 packages all of them returned various dependies issues.

If I tried to install the unixODBC that didn't have the 64 in the package name, they all installed ok with no dependies issues.

Aren't both of these x86_64 packages? I guess I'm not understanding what the difference is between the two, even though they seem the same to me.

Also I'm not clear if there is an rpm command to get info on a rpm package that isn't installed so I can cross-compare them against what did install.

thanks