# Java Program for Find largest prime factor of a number

• Last Updated : 17 Feb, 2018

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


## Java

 // Java Program to find largest// prime factor of numberimport java.io.*;import java.util.*;  class GFG {  // function to find largest prime factorstatic long maxPrimeFactors( long n){    // Initialize the maximum prime    // factor variable with the     // lowest one    long maxPrime = -1;      // Print the number of 2s    // that divide n    while (n % 2 == 0) {        maxPrime = 2;                  // equivalent to n /= 2        n >>= 1;     }      // n must be odd at this point,    // thus skip the even numbers     // and iterate only for odd    // integers    for (int i = 3; i <= Math.sqrt(n); i += 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 maxPrime;}  // Driver codepublic static void main(String[] args){    Long n = 15l;    System.out.println(maxPrimeFactors(n));      n = 25698751364526l;    System.out.println(maxPrimeFactors(n));}}  // This code is contributed by Gitanjali

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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