Zero.
Smallest is 11 & Largest is 77.
101
The smallest prime number in which all of the digits are also prime is 2.The smallest multi-digit prime number in which all of the digits are also prime is 23.
You had me until "product." The product of 4 digits can't be prime.
The two smallest prime numbers are 2 & 3. Their product is thus, 2 x 3 = 6.
The smallest prime number, of course, is 2. The smallest prime number whose digits add up to 2 is, of course, 2. The next-smallest is 11. It is left as an exercise for the reader to determine whether the other numbers whose digits add up to 2 (e.g. 101, 1001, 10001) are prime.
The smallest two-digit prime number whose digits themselves are prime is 23. Both 2 and 3 are prime numbers, and together they form the prime number 23.
The four numbers are: 113, 131, 151 and 191. For the product of the digits to be prime, the number must contain 2 ones - which greatly simplifies the exercise.
It is 27,000.
30
Yes.
The first prime numbers are 2, 3, 5, 7, 11. When multiplied together the product is 2310. It is the smallest number that has the first five numbers as its factors.