<p>0x34363932353433373538323038353135353439</p>

From the Unix / cygwin command line, you can use bc.
```
```
$ bc
ibase=16
34363932353433373538323038353135353439
1164362276596472215941024063897591129839055929
```
```
There is also
an online version
.  If you want to do it in code you should use an arbitrary precision library facility, like Java's BigInteger, Perl's Math::BigInt, Tcl's  math::bignum, or of the many multiple precision arithmetic libraries that are available for C, like
GNU GMP
, or
MPI
.