# Python Program for Find largest prime factor of a number

Given a positive integer \’n\'( 1 <= n <= 1015). Find the largest prime factor of a number.

Input: 6
Output: 3
Explanation
Prime factor of 6 are- 2, 3
Largest of them is \'3\'

Input: 15
Output: 5


## Python3

 # Python3 code to find largest prime  # factor of number  import math     # A function to find largest prime factor  def maxPrimeFactors (n):             # Initialize the maximum prime factor      # variable with the lowest one      maxPrime = -1            # Print the number of 2s that divide n      while n % 2 == 0:          maxPrime = 2         n >>= 1     # equivalent to n /= 2                 # n must be odd at this point,       # thus skip the even numbers and       # iterate only for odd integers      for i in range(3, int(math.sqrt(n)) + 1, 2):          while n % i == 0:              maxPrime = i              n = n / i             # This condition is to handle the       # case when n is a prime number       # greater than 2      if n > 2:          maxPrime = n             return int(maxPrime)     # Driver code to test above function  n = 15 print(maxPrimeFactors(n))     n = 25698751364526 print(maxPrimeFactors(n))     # This code is contributed by "Sharad_Bhardwaj".

Output:

5
328513


Time complexity: Auxiliary space: Please refer complete article on Find largest prime factor of a number for more details!

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