> >>> 434437* * 15 + 588129* * 15 - 588544 * *15
> -604550152144288043930860169354171954730939671404246170822386878582482
(Edit: how do I display two asterisks in a row? It's supposed to be number(asterisk)(asterisk)number.)
This is using Python, which does arbitrary-precision integer arithmetic.
Google's calculator probably uses floating-point numbers internally, and hence starts losing precision.