2, 5, 7, and 11 are all prime numbers. If you multiply three of them together and subtract the fourth number, how many of the resulting numbers are prime numbers?
2，5，7，11都是质数，如果把其中三个数相乘，再减去第四个数，这样得到的数中，是质数的共有多少个．
<result>4</result>