How to find Factorial of a number in Python

In this article, we will learn to find the factorial of a number.

The factorial of a number is the product of all the integers from 1 to that number. For example, the factorial of 6 is 1*2*3*4*5*6 = 720. Factorial is not defined for negative numbers, and the factorial of zero is one.

Recursive Method:

# factorial of a number
# recursive method

def fact(n):
	if (n == 1 or n ==0):
		return 1
	else:
		return n * fact(n - 1)

n = 6
print("Factorial of ", n," is ", fact(n) )

Iterative Method:

# factorial of a number
# iterative method

def fact(n):
	if n < 0:
		return 0
	elif n == 0 or n == 1:
		return 1
	else:
		f = 1
		while(n > 1):
			f *= n
			n -= 1
		return f

n = 6
print("Factorial of ", n," is ", fact(n) )