Weird number entry problem in Calc

I have noticed this for some time now, and have no idea why, but certain numbers it seems I am unable to input into a cell in Calc without their being somehow re-rendered in some odd way, so I am wondering if anyone else has encountered this problem, or can recreate the same behavior or not.

Where I run across this is when entering such things as authorization numbers for payments or orders, that sort of thing. Numbers that are randomly generated, no doubt, and which on occasion, seem to cause Calc to treat them as some sort of math problem or fraction or somesuch, and no amount of Style stripping or number formatting seems to change it.

For example, try entering this into a cell:

393459e29

For me, it gets instantly transmogrified into

3.93459E+034

What the frig is that, and how do I get around it? What am I missing here?

393459e29 is the numeric value 393459*10^29 which for the General format is displayed as 3.93459E+034 (3.93459*10^34)

If you want such input that can be converted to numeric be literally preserved then either precede it with an ' apostrophe, so input '393459e29, or apply the Text number format to the cell before input.