[Python] Python Programming Question Beautiful Numbers (Please I need this!)

An number x is call a beautiful number if:
-D(x) = 1

or

-x % D(x) = 0 (and x / D(x) also need to be beautiful)

*D(x) is the length of x (if x = 123 => length x = 3)

Write a python code to count beautiful number in a range(l,r)

Cursed: (1 <= l <= r <= 10^18). run in less than 4s

Example: l = 5; r = 15:

8 beautiful numbers: 5,6,7,8,9,10,12,14

5 is 1 digit

....

10 % D(x) = 0

I tried this but it's too slow

python

def check_BN(x):
d = len(str(x))
if d == 1 or x % d == 0:
return True
return False

def beautifulNumbers(l,r):
count = 0
for i in range(l,r+1):
if check_BN(i) and check_BN(i//len(str(i))):
count += 1
return count

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