project euler 3- not optimized

pe3.py

#proj euler 3
'''
The prime factors of 13195 are 5, 7, 13 and 29.

What is the largest prime factor of the number 600851475143 ?
'''


factorsList = []
i = 2

while i <= 600851475143 / 3:#maybe make it faster?
	if 600851475143 % i == 0:
		print i
		factorsList.append(i)
	i += 1
	
#now we have all of its factors in a list.


print factorsList
primesList = []

for factor in factorsList:
	i = 2 #start @ 2 always
	prime = True
	while(i < factor):
		if factor % i == 0:
			print "factor", factor, "not prime, divisible by", i
			prime = False
			break
		i += 1
	
	if prime == False:
		primesList.append(factor)

# sort and display
primesSorted = sorted(primesList, reverse=True)
print "Largest prime factor is:", primesSorted[0]
	
print "hit enter to end"
inpt = input(">")