Is there any way to find out what are the libraries linked to an executable?

Yes you can.  The following command will assist you in finding the libraries associated with executibles in unix.

OS:  SunOS 5.10 sun4u sparc SUNW,Sun-Fire-280R

Command:  ldd

Location:   /usr/bin/ldd

On HP there is a similar command called:  chatr

Example:

# ldd /u01/oradba/product/10.2.0.3/bin/lsnrctl

        libclntsh.so.10.1 =>     /u01/oradba/product/10.2.0.3/lib/libclntsh.so.10.1
        libnnz10.so =>   /u01/oradba/product/10.2.0.3/lib/libnnz10.so
        libkstat.so.1 =>         /lib/64/libkstat.so.1
        libnsl.so.1 =>   /lib/64/libnsl.so.1
        libsocket.so.1 =>        /lib/64/libsocket.so.1
        libgen.so.1 =>   /lib/64/libgen.so.1
        libdl.so.1 =>    /lib/64/libdl.so.1
        libsched.so.1 =>         /usr/lib/64/libsched.so.1
        libc.so.1 =>     /lib/64/libc.so.1
        libaio.so.1 =>   /lib/64/libaio.so.1
        libm.so.2 =>     /lib/64/libm.so.2
        librt.so.1 =>    /lib/64/librt.so.1
        libmp.so.2 =>    /lib/64/libmp.so.2
        libmd5.so.1 =>   /lib/64/libmd5.so.1
        libscf.so.1 =>   /lib/64/libscf.so.1
        libdoor.so.1 =>  /lib/64/libdoor.so.1
        libuutil.so.1 =>         /lib/64/libuutil.so.1
        /platform/SUNW,Sun-Fire-280R/lib/sparcv9/libc_psr.so.1
        /platform/SUNW,Sun-Fire-280R/lib/sparcv9/libmd5_psr.so.1

Example 2:

# ldd $ORACLE_HOME/bin/oracle

  libskgxp10.so =>         /u01/oradba/product/10.2.0.3/lib/libskgxp10.so
        libhasgen10.so =>        /u01/oradba/product/10.2.0.3/lib/libhasgen10.so
        libskgxn2.so =>  /u01/oradba/product/10.2.0.3/lib/libskgxn2.so
        libocr10.so =>   /u01/oradba/product/10.2.0.3/lib/libocr10.so
        libocrb10.so =>  /u01/oradba/product/10.2.0.3/lib/libocrb10.so
        libocrutl10.so =>        /u01/oradba/product/10.2.0.3/lib/libocrutl10.so
        libjox10.so =>   /u01/oradba/product/10.2.0.3/lib/libjox10.so
        libclsra10.so =>         /u01/oradba/product/10.2.0.3/lib/libclsra10.so
        libdbcfg10.so =>         /u01/oradba/product/10.2.0.3/lib/libdbcfg10.so
        libnnz10.so =>   /u01/oradba/product/10.2.0.3/lib/libnnz10.so
        libkstat.so.1 =>         /lib/64/libkstat.so.1
        libnsl.so.1 =>   /lib/64/libnsl.so.1
        libsocket.so.1 =>        /lib/64/libsocket.so.1
        libgen.so.1 =>   /lib/64/libgen.so.1
        libdl.so.1 =>    /lib/64/libdl.so.1
        libsched.so.1 =>         /usr/lib/64/libsched.so.1
        libc.so.1 =>     /lib/64/libc.so.1
        libaio.so.1 =>   /lib/64/libaio.so.1
        librt.so.1 =>    /lib/64/librt.so.1
        libm.so.2 =>     /lib/64/libm.so.2
        libmp.so.2 =>    /lib/64/libmp.so.2
        libmd5.so.1 =>   /lib/64/libmd5.so.1
        libscf.so.1 =>   /lib/64/libscf.so.1
        libdoor.so.1 =>  /lib/64/libdoor.so.1
        libuutil.so.1 =>         /lib/64/libuutil.so.1
        /platform/SUNW,Sun-Fire-280R/lib/sparcv9/libc_psr.so.1
        /platform/SUNW,Sun-Fire-280R/lib/sparcv9/libmd5_psr.so.1

HP UX:

chatr oracle
oracle:
shared executable
shared library dynamic path search:
SHLIB_PATH enabled first
embedded path disabled second Not Defined
shared library list:
dynamic /all/oracle/product/8.1.7/lib/libjox8.sl
dynamic /all/oracle/product/8.1.7/lib/libobk.sl
dynamic /usr/lib/librt.2
dynamic /usr/lib/libpthread.1
dynamic /usr/lib/libnss_dns.1
dynamic /usr/lib/libdld.2
dynamic /usr/lib/libm.2
dynamic /usr/lib/libc.2
shared library binding:
deferred
global hash table disabled
plabel caching disabled
global hash array size:1103
global hash array nbuckets:3
shared vtable support disabled
static branch prediction enabled
executable from stack: D (default)
kernel assisted branch prediction enabled
lazy swap allocation disabled
text segment locking disabled
data segment locking disabled
third quadrant private data space disabled
fourth quadrant private data space disabled
data page size: D (default)
instruction page size: D (default)