Why does the return not work in my program? C

Question

So I am a beginner in C and I was trying to use functions in my programs but I cant figure out why my function isn't returning 1 or 0, and if I put a printf("Hello"); in the middle of the loop in the function it isn't appearing in the console. Any help would be appreciated!

int Primo(int x);

int main() {
    Ex4_MED_4();
}

 void Ex4_MED_4(){
    int prime,number;
    printf("Pick a number:");
    scanf("%d",number);
    prime=Primo(number);
    printf("%d",prime);
}

int Primo(int x){
    for(int i=2;i<=x/2;i++){
        if (x%i==0) {
            return 0;
        }
    }
    return 1;
}

Answer 1

I don't know how to mark a comment has a solution, but thanks to @Eugene Sh. I was able to see I am brain dead and forgot to put a & in the scanf() . So scanf("%d",number) --> scanf("%d",&number) . If someone could tell me how to make him the top answer would appreciate!