To check if number provided by the user is Armstrong number or not(using while loop) in Python

Program:

Original_number=int(input("Enter the Number:"))
num=Original_number
k=str(num)
l=len(k)
r=0

while num>0:
    d=num%10
    r=r+pow(d,l)
    num=num//10

if(r==Original_number):
 print("-->>",Original_number,"is Armstrong Number")
else:
 print(Original_number,"is Not a Armstrong Number")

Expected O/P:

Enter the Number:153
-->> 153 is Armstrong Number