You had me until "product." The product of 4 digits can't be prime.
101 103 107 109
The sum of the first four prime numbers is 17.
you take the four digits and multiply 4 by 4 you get 16 digits
The next four prime numbers greater than 31 are 37, 41, 43, and 47.
You had me until "product." The product of 4 digits can't be prime.
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.
There are four pair of mirror primes.
1234, 2637, 7777, 2727 are examples of a four digit number. So any random four numbers are four digits.
You know that the odd digits have to be in the units places, and the evens in the tens place, so the general solution is: 80 + 60 + 40 + 20 + 9 + 7 + 3 + 1 = 220
101 103 107 109
61 is prime. You cannot make 61 by multiplying four digits.
The sum of the first four prime numbers is 17.
you take the four digits and multiply 4 by 4 you get 16 digits
None of those four numbers are prime numbers.
47 does not have 4 prime numbers (factors or divisors).
four The lowest 5 digits prime number is 10007