Iterative approach:
def calculate_factorial(n):
factorial = 1
for i in range(1, n + 1):
factorial *= i
return factorial
Recursive:
def calculate_factorial(n):
if n == 0:
return 1
else:
return n * calculate_factorial(n-1)
It would be great if you could share the code that you tried.
Answer from DASH on Stack OverflowGeeksforGeeks
geeksforgeeks.org › python › python-program-for-factorial-of-a-number
Factorial of a Number - Python - GeeksforGeeks
Given an integer n, the task is ... and combinatorics. For Example: Input: n = 6 Output: 720 Explanation: 6! = 6 × 5 × 4 × 3 × 2 × 1 = 720 · Let's explore different methods to find the factorial of a number in ...
Published November 29, 2025
Vultr
docs.vultr.com › python › examples › find-the-factorial-of-a-number
Python Program to Find the Factorial of a Number | Vultr Docs
December 27, 2024 - For example, the factorial of 5 (denoted as 5!) is calculated as 5 * 4 * 3 * 2 * 1, which results in 120. Factorials are commonly used in permutations, combinations, and other statistical calculations.
Videos
GeeksforGeeks
geeksforgeeks.org › python › factorial-in-python
factorial() in Python - GeeksforGeeks
The factorial of a number n (written as n!) is the product of all positive integers from 1 to n. ... Python provides a function math.factorial() that computes factorial without writing the entire loop manually. ... Parameters: x -> number whose factorial you want (must be a non-negative integer). Example 1: This example uses math.factorial() to compute factorial directly using Python’s inbuilt function.
Published December 18, 2025
Top answer 1 of 5
1
Iterative approach:
def calculate_factorial(n):
factorial = 1
for i in range(1, n + 1):
factorial *= i
return factorial
Recursive:
def calculate_factorial(n):
if n == 0:
return 1
else:
return n * calculate_factorial(n-1)
It would be great if you could share the code that you tried.
2 of 5
0
A possible method using a while loop:
factorial_base = int(input('Enter a positive integer:\n')) # The number to factorialize.
factorial = 1
if factorial_base > 0: # 0! = 1, so if the base is 0, just leave the factorial value as default (1).
while factorial_base != 1:
factorial *= factorial_base
factorial_base -= 1
Essentially, this will multiply 1 by the given number to factorialize (i.e. n), then by (n - 1), then by (n - 2), and so on, until the multiplication factor reaches 1.
Hope this helps.
Programiz
programiz.com › python-programming › examples › factorial
Python Program to Find the Factorial of a Number
# Python program to find the factorial ... from the user # num = int(input("Enter a number: ")) # call the factorial function result = factorial(num) print("The factorial of", num, "is", result)...
AlmaBetter
almabetter.com › bytes › articles › factorial-program-in-python
Factorial Program in Python(Factorial of a Number in Python)
October 19, 2024 - Learn to write a factorial program in Python using for loops, while loops, recursion, and functions with code examples, detailed explanations and use cases ... The factorial of a number is an essential concept in mathematics and programming. It is denoted as n!, which represents the product of all positive integers from 1 to n. For example, the factorial of 5 (written as 5!) is calculated as:
w3resource
w3resource.com › python-exercises › python-functions-exercise-5.php
Python Exercise: Calculate the factorial of a number - w3resource
Factorial of 5: 120 Factorial of -12: Number can't be negative or floating point! Factorial of 1.22: Number can't be negative or floating point! Factorial of 100: 93326215443944152681699238856266700490715968264381621468592963895217599993229...
Vultr
docs.vultr.com › python › examples › find-factorial-of-number-using-recursion
Python Program to Find Factorial of Number Using Recursion | Vultr Docs
November 21, 2024 - number = 5 if number >= 0: print("Factorial of", number, "is", factorial(number)) else: print("Enter a positive integer") Explain Code · This script sets a number 5 then checks if it's non-negative before calling the factorial function.
PYnative
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Python Find Factorial of a Number [5 Ways] – PYnative
March 31, 2025 - ... In this example, we are applying the lambda function (x * y) to all values in the list [1, 2, 3, 4]. So, the output is 24 (1*2*3*4). from functools import reduce n = 5 if n < 0: print("Factorial not defined for negative numbers") factorial = reduce(lambda x, y: x * y, range(1, n + 1), 1) ...
Codingem
codingem.com › home › factorial with a while loop in python
Factorial with a While Loop in Python - codingem.com
April 10, 2023 - print(factorial(5)) Output: 120 · You now know what is the factorial of a number and how it is commonly calculated using recursion. But there are some alternatives, that is: A built-in function · While loop · For loop · Let’s go through ...
W3Schools
w3schools.com › python › ref_math_factorial.asp
Python math.factorial() Method
The factorial of a number is the ... 1. For example, the factorial of 6 would be 6 x 5 x 4 x 3 x 2 x 1 = 720 ... If you want to use W3Schools services as an educational institution, team or enterprise, send us an e-mail: sales@w3schools.com ...
Top answer 1 of 10
251
The easiest way is to use math.factorial (available in Python 2.6 and above):
import math
math.factorial(1000)
If you want/have to write it yourself, you can use an iterative approach:
def factorial(n):
fact = 1
for num in range(2, n + 1):
fact *= num
return fact
or a recursive approach:
def factorial(n):
if n < 2:
return 1
else:
return n * factorial(n-1)
Note that the factorial function is only defined for positive integers, so you should also check that n >= 0 and that isinstance(n, int). If it's not, raise a ValueError or a TypeError respectively. math.factorial will take care of this for you.
2 of 10
121
On Python 2.6 and up, try:
import math
math.factorial(n)
WsCube Tech
wscubetech.com › resources › python › programs › factorial
Python Program to Find Factorial of a Number (Factorial Code)
October 28, 2025 - Learn how to write a Python program to find the factorial of a number. Understand efficient factorial code to solve factorial problems quickly and easily.
Tutorial Gateway
tutorialgateway.org › python-program-to-find-factorial-of-a-number
Python Program to find Factorial of a Number
March 31, 2025 - number = int(input(" Please enter any Number : ")) fact = 1 for i in range(1, number + 1): fact = fact * i print("The factorial of %d = %d" %(number, fact)) The user entered integer in the above program example is 4. Please refer to math functions, ...
Reddit
reddit.com › r/learnpython › factorials
r/learnpython on Reddit: Factorials
October 11, 2021 -
I have an assignment for class about a topic we never went over. Would appreciate help how to do it.
Write a script that inputs a nonnegative integer and computes and displays is facotrial. Try your script on the integers 10, 20, 30 and even larger values. Did you find any integer input for which Python could not produce an integer factorial value?
I have no idea where to start
Top answer 1 of 3
3
Well. What is Factorial? Factorial 5 is 5! = 1 * 2 * 3 * 4 * 5. All you need is a starting variable that is initialized to 1, and then you need to loop over all numbers from 1 (can be optimized to start at 2) to the_factorial_you_want_to_calculate. For every number that you loop over you multiply your starting variable by that number. After you looped over all the numbers, you have the factorial value in your starting variable.
2 of 3
1
You can use math.factorial for calculation. Once the input number is too large, you well run out of memory to store it, which answers your second question.
Great Learning
mygreatlearning.com › blog › it/software development › python program to find the factorial of a number
Python Program to Find the Factorial of a Number
October 24, 2024 - ... Factorial of a number is denoted by n! is the product of all positive integers less than or equal to n: ... So what is 10!? Multiply 10 with all the positive integers which are less than 10. ... To find '5!' again, do the same process.
Shiksha
shiksha.com › home › it & software › it & software articles › programming articles › how to find the factorial of a number using python
How to Find the Factorial of a Number Using Python - Shiksha Online
August 16, 2024 - How to Find the Factorial of a Number Using Python ... In this article, we will discuss different methods to find the factorial of a number in python using for, while, ternary operator and math module. While practicing Python programming as a beginner, or even during Python interviews, one of the most common programs you will be asked to write is going to be Python factorial.
Unstop
unstop.com › home › blog › factorial program in python | examples & complexity analysis
Factorial Program In Python | Examples & Complexity Analysis
February 4, 2025 - ... # Function to find factorial ... return n * factorial_recursive(n - 1) # Example usage number = 5 print(f"The factorial of {number} is {factorial_recursive(number)}")...
Simplilearn
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Factorial Program in Python: Explained with Examples
November 9, 2023 - Learn to code a factorial program in Python with our easy guide. Master loops & recursion techniques for your coding toolbox. Continue reading!
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Python Guides
pythonguides.com › factorial-of-a-number-in-python
Factorial Of A Number In Python
March 20, 2025 - Check out Download and Extract ZIP Files from a URL Using Python · Recursion provides an efficient way to calculate factorials that mirrors the mathematical definition: def factorial_recursive(n): """Calculate factorial using recursion.""" if n < 0: raise ValueError("Factorial is not defined for negative numbers") # Base case if n == 0 or n == 1: return 1 # Recursive case return n * factorial_recursive(n - 1) # Example usage number = 6 print(f"The factorial of {number} is: {factorial_recursive(number)}")