Prime Number Archives - GeeksforGeeks

Largest Prime Number possible from a subsequence of a Binary String

Given a Binary string, the task is to find the largest Prime Number possible by the decimal representation of a subsequence of the given binary… Read More

binary-representation

binary-string

Prime Number

Bitwise XOR of first N natural numbers that are product of two distinct Prime Numbers

Given a positive integer N, the task is to calculate the Bitwise XOR of first N numbers which are a product of exactly two distinct… Read More

Count strings having sum of ASCII values of characters equal to a Prime or Armstrong Number

Expert

Given an array arr[] of size N containing strings, the task is to count the number of strings having sum of ASCII values of characters… Read More

Find the array element having equal sum of Prime Numbers on its left and right

Medium

Given an array arr[] of size N, the task is to find the index in the given array where the sum of the prime numbers… Read More

Find the array element having equal count of Prime Numbers on its left and right

Given an array arr[] consisting of N positive integers, the task is to find an index from the array having count of prime numbers present… Read More

Count numbers up to N having exactly 5 divisors

Given a positive integer N, the task is to count the number of integers from the range [1, N] having exactly 5 divisors. Examples: Input:… Read More

Consecutive Prime numbers greater than equal to given number.

Medium

Question: Given a number n, the task is to find two consecutive prime such that the product of these two prime is greater than or… Read More

Prime Number

Greedy

Number which is co-prime with all integers from a given range

Given two positive integers L and R, the task is to find an integer X greater than 1 such that X is co-prime with all… Read More

Segregate Prime and Non-Prime Numbers in an array

Medium

Given an array arr[] of size N, the task is to rearrange the array elements such that all the Prime numbers are placed before the… Read More

interview-preparation

Paytm

Prime Number

sieve

two-pointer-algorithm

Arrays

Mathematical

Absolute difference between the count of odd and even factors of N

Given a positive integer N, the task is to find the absolute difference of the count of odd and even factors of N. Examples: Input:… Read More

Program to find the Nth Composite Number

Given a positive integer N, the task is to find the Nth Composite Number. Examples: Input: N = 1Output: 4 Input: N = 3 Output: 8… Read More

Count array elements whose count of divisors is a prime number

Given an array arr[] consisting of N positive integers, the task is to find the number of array elements whose count of divisors is a… Read More

Count prime numbers up to N that can be represented as a sum of two prime numbers

Given a positive integer N, the task is to find the count of prime numbers less than or equal to N that can be represented… Read More

Prime Number

sieve

Mathematical

Smallest Semi-Prime Number with at least N difference between any two of its divisors

Given a positive integer N, the task is to find the smallest semi-prime number such that the difference between any of its two divisors is… Read More

Check if a number can be represented as a sum of a Prime Number and a Perfect Square

Given a positive integer N, the task is to check if N can be represented as a sum of a Prime Number and a Perfect… Read More