I love to show that kind of shit to AI boosters. (In case you're wondering, the numbers were chosen randomly and the answer is incorrect).
They go waaa waaa its not a calculator, and then I can point out that it got the leading 6 digits and the last digit correct, which is a lot better than it did on the "softer" parts of the test.
Also, if the LLM had reasoning capabilities that even remotely resembled those of an actual human, let alone someone who would be able to replace office workers, wouldn't they use the best tool they had available for every task (especially in a case as clear-cut as this)? After all, almost all humans (even children) would automatically reach for their pocket calculators here, I assume.