Step 1: Arrange letters alphabetically.
Alphabetical order: \[ A, D, P, R, U, Y \] Step 2: Count permutations before each letter.
Compute permutations starting with letters smaller than the current letter at each position.
Step 3: Sum all preceding permutations.
Total number of words before ``UDAYPUR'' is \[ 1579 \] Step 4: Add 1 for the word itself.
\[ \text{Rank}=1579+1=1580 \]