If you put 0, 1 and z on the stack, in that order, then the UPTN command returns the upper tail probability.
This will give you 0.5 minus your value of 0.4772, when rounded to 4 decimal places).
The 0 and 1 are for the mean and standard deviation, which are 0 and 1, respectively, for the z distribution.
For anyone else finding this old post via Google search, the second argument (1 here) is in general NOT the standard deviation, but rather the variance (square of the standard deviation). In this example the variance is also 1, of course.
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