scala function to test for prime number

/** simple scala function to test is a number is a prime number **/

def isPrime(p: Int): Boolean = {
    val p1=math.abs(p)
    if (p1 <= 3) return true
    var t: Int = math.sqrt(p1).asInstanceOf[Int]
    for ( i <- 2 to t if p1 % i == 0) return false
    return true
  }