A positive integer N fulfills the following demands:.

N is a 7 digit number.

N's digits can be arranged as seven distinct members of an arithmetic progression(either ascending or descending) .

N is a multiple of 11.

How many positive integers like N exist?

Evaluate the lowest and the highest N.

BONUS : How about 8 digits? Nine? All ten?

Rem: It is D4 for fully explained and errorless P&P result,might be significantly lower for software solution.