Threaded RSA cracker

RSAcrack.py

# Importing modules
from time import perf_counter
from hashlib import md5
from random import randint
from multiprocessing import Queue, Process, Pool
import sys

# Global variables
q = Queue()

# Check if prime is factor of RSA number
def rsaFcheck(RSAnum, prime):
    if RSAnum % prime == 0:
        factors = (prime, (RSAnum / prime))
        return True
    return False

# Check RSA factors main
def crack(RSAnum, down, up):
    for i in range(down+1, up):
        cand = (2*i) + 1
        if rsaFcheck(RSAnum, cand):
            factor1, factor2 = (cand, int(RSAnum / cand))
            print(str("The prime factors are: " + str(factor1) + ", " + str(factor2)))
            q.put((factor1, factor2))
            break
        if not q.empty():
            break

# Main threading
def main():
    if len(sys.argv) != 3:
        sys.exit("Usage: python3 RSAcrack.py <RSA number> <Thread number>")
    RSAnum = int(sys.argv[1])
    threadNum = int(sys.argv[2])
    # Generate range numbers
    minimum = int(10 ** int((len(str(RSAnum)) - 2) / 2))
    maximum = int((10 ** (int(len(str(RSAnum)) + 1) / 2)) -1)
    inc = maximum / threadNum
    # multiprocessing
    threads = []
    pool = Pool()
    for i in range(1,int(threadNum+1)):
        down = minimum + int(inc*(i-1))
        up = int(inc*i)
        thread = pool.apply_async(func = crack, args = (RSAnum, down, up))
        threads.append(thread)
    pool.close()
    pool.join()

if __name__ == '__main__':
    tic = perf_counter()
    main()
    toc = perf_counter()
    print("Execution time: " + str(toc - tic))
    sys.exit(0)