Do you know its property ?-7

Probability Level 4

The number of non-negative integral solutions of the inequality $x+y+z \leq 1729$ is RN.

Find the digit sum of RN.

Details and Assumptions ;
1. Digit sum refers to the sum of the digits. For instance, digit sum of $1729$ is $1+7+2+9=19$
2. RN I used for $Ramanujan Number$ (Just for fun)

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