#ERROR! message when I try to use "Right({String},4)" when String = numerical result of a date based formula

I have created a random number generator string {RNGS} using this formula: VALUE(DATETIME_FORMAT(AddDate, ‘mm’)) # Autonumber # Autonumber.

(Note: I have purposefully substituted # for an asterisk/mutliply function in this post)

A sample result is 238425 (33 # 85 # 85). I’d like to use just the first 4 digits for my random number field

I’ve tried both RIGHT(VALUE(DATETIME_FORMAT(AddDate, ‘mm’)) # Autonumber # Autonumber,4)
and
RIGHT({RNGS},4)

Both of these generate the #ERROR! message. Please help!