This integral crashes by Virtual prime...

[webmasterpdx]

With CAS, whats interesting is if I use 6 as the integral upper limit, it gives me a message that says that it's giving me both exact and approximate values as it got an error checking them against one another.
Then when I hit enter again, it gives me the gamma result and the numeric displayed like this:
[(gamma stuff) 5.96...E91]

However, if I use 6. (with the decimal point), it gives me just the numeric solution 5.96...E91

Then when I switch to home mode, I get an error. I have to change x to X, and when I do that, I get a weird answer of :00.000.?>:

What does this answer mean?

Finally, when in home mode if I do approx(place the integral here), I get the weird answer above, followed by the correct numeric answer like this:
[:00.000.?>: 5.96...E91]
What do square braces mean again? Is it an array?

Thx
-Donald