Basically, don't look for a trick in this question. This is a strictly mathematical question. Just divide the amount of seconds to move the whole tower by the average amount of seconds in a year (be sure not to use a calculator which loses precision).

If you type

*help* as the answer, you will see a help about the average number of seconds in a year (average, because some years are leap years and some are not, so not all years have the same number of seconds), so just divide the two numbers and round mathematically to the nearest integer. That's it.

And you're right, the legend is for sure untrue, because it assumes that at the very beginning at the world they already had the tower on the first needle, while we know that at that time there was no gold, no diamonds, no priests, no temples and no Earth

but it's simply unimportant here.

TPReal