"Primes whose digits sum to a prime" refers to a special type of prime number where the sum of its individual digits is also a prime number. For example, 23 is a prime whose digits (2 and 3) sum to 5, which is also a prime number.
To determine if a number is a "Prime whose digits sum to a prime", you need to first check if the number itself is a prime number. If it is, then you need to sum up all its individual digits and check if that sum is also a prime number. If both conditions are met, then the number is a "Prime whose digits sum to a prime".
There are no known special properties or patterns for "Primes whose digits sum to a prime". These types of primes are considered to be rare and occur randomly in the sequence of prime numbers.
No, not all numbers have a "Prime whose digits sum to a prime". For example, 10 is not a "Prime whose digits sum to a prime" because its digits (1 and 0) sum to 1, which is not a prime number. However, there are infinitely many numbers that do have this property.
As of now, there are no known practical applications for "Primes whose digits sum to a prime". These types of primes are mostly studied for their mathematical curiosity and do not have any significant real-world applications.