You appear not to know why you want to do what you state, nor have you stated the requirements in any detail.
Do you have a particular address in mind to store the string in ?
Do you mean that you want to store the string in EEPROM or maybe PROGMEM ?
Is it a string (an array of chars terminated by a zero) or a String (an object created using the String library ?
The more detail that you can give the more chance there is of an answer to your question