3 13 23 43 53 73 83
The largest three digit prime number whose digits are all primes is 773.
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 largest 3 digit number whose digits are all primes is 777. The largest 3 digit number with different prime digits is 753.
67
6859
84
The largest three digit prime number whose digits are all primes is 773.
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.
There is no three digit prime number whose square root is a prime number. Prime numbers have no factors other than 1 and themselves. Any number having a prime number as a square root is a composite number.
The largest 3 digit number whose digits are all primes is 777. The largest 3 digit number with different prime digits is 753.
67
754 Piece of cake!
97969
9409
6859
121
What is the units digit of the least whole number greater than 1000 whose digits are all different?