Little explorations with HP calculators (no Prime)

[Han]

Those are two very different numbers. The first one is equal to 27^27 (39 decimal digits) which is much smaller than the second number (3 638 334 640 025 decimal digits). Since each digit is a nibble (4 bits), there is not enough memory to hold all the digits.

The order of operations (due to the explicit parentheses) makes the difference.