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1. Print Numbers 1–1002. Print Even Numbers in Range3. Print Odd Numbers in Range4. Sum of Digits5. Reverse Digits of a Number6. Calculate Factorial (Loop)7. Fibonacci Series8. Palindrome Number Check9. Count Digits in a Number10. GCD of Two Numbers (Loop)11. LCM of Two Numbers (Loop)12. Print Prime Numbers in Range13. Count Prime Numbers in Range14. Check Composite Number15. Power of 2 Checker16. Print Number Pattern17. Print Star Pattern18. Armstrong Numbers in Range19. Strong Numbers in Range20. Sum of Series 1/1 + 1/2 + … + 1/N21. Print Multiplication Series22. Print Pyramid Pattern23. Print Inverted Pyramid Pattern24. Print Floyd's Triangle25. Print Pascal's Triangle

Reverse Digits of a Number in Python

Reverse the digits of an integer using a loop.

BeginnerLoop ProgramsExample 5 of 25
reverse-digits-of-a-number.py
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1# Program to reverse digits of a number
2

3num = int(input("Enter an integer: "))
4

5rev = 0
6temp = abs(num)
7

8while temp > 0:
9    digit = temp % 10
10    rev = rev * 10 + digit
11    temp //= 10
12

13if num < 0:
14    rev = -rev
15

16print("Reversed number is", rev)

Output

Enter an integer: 1234
Reversed number is 4321

What's going on

We build the reversed number by shifting previous digits left (×10) and adding the current last digit each iteration.

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