Check if number is prime in class constructor?

Question

I would like to check when instantiating a object if the input are valid or not (prime); within the constructor parameters of the class. How would I accomplish this in typescript? I have already created a lambda and static function for checking if a variable is prime, which one would be best to use in the constructor method? Here is my code:

class RSA {

    public check = (n: number) => {
        if (n <= 1)
            return false;
        var i: number = 2;
        while(i*i <= n) 
            n%i == 0 ? false : i += 1;
        return n;
    }

    /**
     * Create a new RSA object
     * @param p 
     * @param q 
     * @returns object capable of encryption/decryption
     */
    constructor(p: number, q: number) {
        this.generateKeys(p, q);
    }

    /**
     * Returns boolean to verify if 'n' is prime 
     * @param n input to verify (e.g. p and q)
     * @returns boolean of n
     */
    public static isPrime(n: number): number | boolean {
        if (n <= 1)
            return false;
        var i: number = 2;
        while(i*i <= n) 
            n%i == 0 ? false : i += 1;
        return n;
    }
}