def primes(n):
    if n<=2:
        return []
    sieve=[True]*(n+1)
    for x in range(3,int(n**0.5)+1,2):
        for y in range(3,(n//x)+1,2):
            sieve[(x*y)]=False

    return [2]+[i for i in range(3,n,2) if sieve[i]]

def primefactors(n):
	primelist = primes(100)
	lpf = 2
	for prime in primelist:
		print "Checking prime: "+str(prime)
		if n%prime == 0 and prime > lpf:
			print "Better prime found: "+str(prime)
			lpf = prime
	return "{!s},{!s}".format(lpf,n/lpf)