Python Program to Find the Factorial of a Number Tutorial

In this Tutorial you will learn to write a Python Program to find the factorial of a number using Iterative Method ( for loop ).

The factorial of a positive integer n, which is denoted as n!, is the product of all positive integers less than or equal to n.

That is n! = n * (n-1)*(n-2)*....*3*2*1

So 4! = 4 * 3 * 2 * 1 which is equal to 24.

Factorial for the numbers 0 and 1 is 1. That is 0! = 1 and 1! = 1.
For negative numbers factorial value doesn't exists.

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[mohamedh.]

I love your explanation. Most videos I've come across do not explain this thoroughly. keep it up!

[Roboticdock]

I like the use of range function in the context of factorial. Very nice job!

[shreyasahu]

loved your explanation I was literally searching for an explanation for the factorial. Couldn't get any clearer.

[rajuthoppil]

This channel is so underrated!
Share!

[sharonmutiso]

clear and the best explanation in the YouTube. Thank you.

[likhomava]

I really enjoyed the way you explained the concept of factorial. dont you mind creating a python playlist where u will be doing similar task. I could learn a lot from you.

[dishamehta]

Best Explaination till now in Youtube!!1❤😍

[demopoint]

You explained this very well, thanks!

[ShadeWhite_kay]

I liked the latter part. Keep it coming

[vovantrung]

such a very clear and easy to understand video. Thank you

[rotes]

Awesomely done and explained! Well done brother

[mugisha_art]

Bruh! your are good at explaning codes

[JJJJ-gluf]

Good explanation of factorials. Thanks.

[kapilthapa-oy]

Sir, where would u put the exit statement if i want to execute this program again n again until the user wans to exit the program.

[ataberdi]

Hello, what software do you use to draw/write numbers with highletrs? You used it in this video.😀🤩

[ankitadeore]

number=int(input("Enter a number:"))

factorial=1

if (number < 0):
print("cant compute factorial of negative number")
elif (number <2):
print("{}!={}".format(number, factorial))

else:
for i in range(number, 1, -1):
# print(number)
factorial=factorial*number
print("{}!={}".format(number, factorial))

output:Enter a number:4
4!=64


The output of this program is coming wrong it should be 24

[autarroy]

Thanks, a very good explanation step by step.
How to make this as application in GUI Tkinter