Otaining a social security number

Bonjour! I am a Spanish engineer who is starting to work in France with a permanent contract this October. My company asked me for a social security number and after reading some of the questions in this forum I am a bit confused. I understand that I need to present the following documents to the CPAM:

• a copy of your work contract or your first pay slip (if you have one)
• a copy of your passport or identity card
• a certified copy or the original of your birth certificate (long version with your parents'name)
• RIB (bank account details with IBAN number)
• three utility bills (to prove that you are living in France)
• form S 1106

Regarding the three utility bills, for me it is not possible because I have been in France for 5 days only. Does it mean that I have to wait to stay in France for 3 months to ask for the social security number? Please I would be really glad if you could check that these are the required documents that I have to present and also answering my doubts regarding the utility bills.

Thank you very much.