How fast should a Python factoring script be?

How fast should a Python factoring script be?

Just how efficient is "good enough" for all intents and purposes? I wrote
a script to simply list off all numbers that divide into an input, x, as
pairs (i, n//i) and was just curious how efficient I should be going for?
what is the acceptable rate at which the script starts to lose its
efficiency? This is my code (although advice is appreciated, I just want
to give an idea as to how it works).
import time
print('''This program determines all basic factors of a given number, x,
as ordered pairs, (a, b) where ab=x.
Type "quit" to exit.''')
timer = input('Would you like a timer? (y/n) ')
while 1:
try:
x =(input('x = '))
T0 = time.time()
b = []
n = int(x)**0.5
ran = list(range(1, int(n)+1))
if int(x) % 2 == 1:
ran = ran[::2]
for i in ran:
if int(x) % i == 0:
m = (i, int(x)//i)
b.append(m)
else:
pass
except ValueError as error_1:
if x == 'quit':
break
else:
print(error_1)
except EOFError as error_2:
print(error_2)
except OverflowError as error_3:
print(error_3)
except MemoryError as error_4:
print(error_4)
T1 = time.time()
total = T1-T0
print(b)
print(str(len(b)) + ' pairs.')
if timer == 'y':
print("%.5f" % total + ' seconds.')
some of the results are:
x = 9
[(1, 9), (3, 3)]
2 pairs.
0.00000 seconds.
x = 8234324543
[(1, 8234324543)]
1 pairs.
0.07404 seconds.
x = 438756349875
[(1, 438756349875), (3, 146252116625), (5, 87751269975), (15,
29250423325), (25, 17550253995), (75, 5850084665), (125,
3510050799), (375, 1170016933), (557, 787713375), (1671, 262571125),
(2785, 157542675), (8355, 52514225), (13925, 31508535), (41775,
10502845), (69625, 6301707), (208875, 2100569)]
16 pairs.
0.88859 seconds.
So this program can be pretty quick, but then the speed drops rather
rapidly once you get up to higher numbers. Anyways, ya, I was just
wondering what is considered acceptable by todays standards?