c++ std invalid argument while comparing big values

When I run the following code it gives me this error:

string val = "847645262";
if (stoull(val) > ULONG_MAX) {
     cout << "Bigger";
}

libc++abi.dylib: terminating with uncaught exception of type std::invalid_argument: bitset string ctor has invalid argument

And opens up this code in stdexcept from The LLVM Compiler Infrastructure file

_LIBCPP_NORETURN inline _LIBCPP_ALWAYS_INLINE
void __throw_invalid_argument(const char*__msg)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    throw invalid_argument(__msg); // < - IT STOPS HERE
#else
    ((void)__msg);
      _VSTD::abort();
#endif
}

I also tried changing ULONG_MAX in UINT64_MAX but throws the same error, so I manually wrote 18446744073709551615UL and 0xFFFFFFFFFFFFFFFF but changing the base doesn't solve the problem.

Therefore I thought the problem was the stoull function but it works perfectly when compared with small integers like 25 or 76.

What am I doing wrong?