# Number trouble in here [duplicate]

I have been given 24 hours to solve this.

So, my friend has given me 10 examples.

$$1024 = 1$$

$$1000 = 3$$

$$2880 = 5$$

$$6591 = 2$$

$$2113 = 0$$

$$1345 = 0$$

$$1987 = 3$$

$$8888 = 8$$

$$5632 = 1$$

$$6124 = 1$$

So, the question is

$$2456=?$$

• Okk, I didn't know that this was already posted beforehand... I would delete it. Sorry for any inconvenience.. – Sid Aug 28 '16 at 9:48
• No need to delete it. Nothing wrong with leaving a dupe here. – Mithical Aug 28 '16 at 9:49
• You could now ask your friend to solve a variation of a similar puzzle I posted :) – Jonathan Allan Aug 28 '16 at 13:51
• @JonathanAllan Yeah... maybe I should give him a month time for that.. – Sid Aug 28 '16 at 14:14