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# The reverse of a number using python

Faith Mueni Kilonzi
I am a curious software engineer and a data science enthusiast, with a passion for problem-solving through the implementation of high-quality software products. I enjoy learning and teaching.

Given a number, reverse its digits and print the new number.
For example:
Input : num = 8972
Output: 2798

There are a couple of ways to solve this:

# 1. Reverse Number using String slicing

We convert the given number to string using str()
Reverse it using string slicing
Convert the reversed string to int and return the int.

``````def reverseNumber(n):
reversed_number = int(str(n)[::-1])
return reversed_number
``````

# 2. Reverse Number using While Loop

Using a while loop, iterate through the list of the digits from the last one and append the digits into a new number.

``````def reverseNumber(n):
reversed_number = 0
while(n!=0):
r=int(n%10)
reversed_number = reversed_number*10 + r
n=int(n/10)
return reversed_number
``````