the first if clause always returns 1

Question

this solution should return 1 (i.e false) if n is prime, otherwise it returns 0,

the problem is that it always returns 1 because of the first if clause (I've specified a number in the debugging properties as usual)

 if (argc != 2) {
        return 1; 
    }

---

#include <stdio.h> // for ptrintf function
#include <math.h> // for square root function
#include <stdlib.h> // for strtol function 

int is_prime(int n, int i) {
    
    if (i == sqrt(n)) {
        return 0; 
    }
    if (n % i == 0) {
        return 1; 
    }
    return is_prime(n, i + 1); 
    
    /*  for (int i = 2; i <= sqrt(n); i++) {
        if (n % i == 0) {
            return 1; 
        }
    }  
    return 0; */ 
}

int main(int argc, char* argv[]) {
    if (argc != 2) {
        return 1; 
    }
    int n = strtol(argv[1], NULL, 10); 
    
    if (n < 0) {
        return 1;
    }
    int boolean_n = is_prime(n, 2); 

    return 0; 
}