💻 Prime Number Checker

def is_prime(n):
    if n < 2: return False
    if n == 2: return True
    if n % 2 == 0: return False
    for i in range(3, int(n**0.5) + 1, 2):
        if n % i == 0:
            return False
    return True

def primes_upto(limit):
    return [n for n in range(2, limit+1) if is_prime(n)]

def prime_factors(n):
    factors = []
    d = 2
    while d * d <= n:
        while n % d == 0:
            factors.append(d)
            n //= d
        d += 1
    if n > 1:
        factors.append(n)
    return factors

print("=== Prime Number Checker ===")
while True:
    print("
1. Number prime hai ya nahi check karo")
    print("2. N tak ke sab prime numbers")
    print("3. Prime factors nikalo")
    print("4. N consecutive primes dhundho")
    print("5. Baahar jao")
    ch = input("Choice: ")
    if ch == "1":
        n = int(input("Number: "))
        if is_prime(n):
            print(f"{n} PRIME number hai!")
        else:
            factors = prime_factors(n)
            print(f"{n} prime NAHI hai. Factors: {factors}")
    elif ch == "2":
        limit  = int(input("Limit: "))
        primes = primes_upto(limit)
        print(f"1 to {limit} prime numbers ({len(primes)} total):")
        print(f"  {primes}")
    elif ch == "3":
        n = int(input("Number: "))
        print(f"{n} ke prime factors: {prime_factors(n)}")
    elif ch == "4":
        n      = int(input("Kitne prime numbers chahiye: "))
        primes = []
        num    = 2
        while len(primes) < n:
            if is_prime(num):
                primes.append(num)
            num += 1
        print(f"Pehle {n} prime numbers: {primes}")
    elif ch == "5":
        break