Prime factorization - list

Question

I am trying to implement a function primeFac() that takes as input a positive integer n and returns a list containing all the numbers in the prime

Answer 1

This is the code I made. It works fine for numbers with small primes, but it takes a while for numbers with primes in the millions.

def pfactor(num):
div = 2
pflist = []
while div <= num:
    if num % div == 0:
        pflist.append(div)
        num /= div
    else:
        div += 1
# The stuff afterwards is just to convert the list of primes into an expression
pfex = ''
for item in list(set(pflist)):
    pfex += str(item) + '^' + str(pflist.count(item)) + ' * '
pfex = pfex[0:-3]
return pfex