Letters of UDAYPUR: A, D, P, R, U, U, Y (U repeated twice).
Words starting with a letter before U: letters A, D, P, R each give 2!6!=360 arrangements ⇒4×360=1440.
Fix U at position 1. Remaining: A, D, P, R, U, Y (all distinct).
Words starting with UA: 5!=120.
Fix UD at positions 1-2. Remaining: A, P, R, U, Y. No letter before A, so fix UDA.
Remaining: P, R, U, Y. Letters before Y: P, R, U give 3×3!=18.
Fix UDAY. Remaining: P, R, U. No letter before P, fix UDAYP.
Remaining: R, U. Letter before U: R gives 1!=1.
Fix UDAYPU, last letter R: the word itself.
Rank =1440+120+18+1+1=1580.