scanf("%d", number); //replace this line with this: ( scanf("%d", &number); )
also replace this line: ( case '1': ) with this: ( case 1: )

In the first one you missed the & before the variable number.
In the second one you put the number '1' between single quotations so you are converting the number to a character so you need to remove the single quotations.

I hope it will help you to solve your problem