67
what number is prime to 40 29 - it's a prime number (divisible only by 1 and itself) and if you sum the two digits 2 + 9 = 11
59
If you multiply two prime numbers, the product (result) will be a composite number, not a prime number. A prime number has exactly two factors, 1 and itself. The product of two prime numbers will have those two numbers as factors, as well. The sum of two prime numbers might be prime if one of those two numbers is 2, the only even prime number, but otherwise it will not be a prime because two odd numbers will have an even sum, which means it is divisible by 2. Examples: 2 + 3 = 5 (prime) 3 + 7 = 10 (not prime) 13 + 17 = 30 (not prime) If you multiply two prime numbers, the sum of the digits of the product might or might not be prime. Examples: 2 x 7 = 14, sum of digits is 5 (prime) 2 x 11 = 22, sum of digits is 4 (not prime) 3 x 5 = 15, sum of digits is 6 (not prime) 3 x 7 = 21, sum of digits is 3 (prime) 5 x 7 = 35, sum of digits is 8 (prime)
23
If the sum of digits of a number is a multiple of 3 then it is divisible by 3. Sum of digits of 234567 = 2+3+4+5+6+7 = 27 = 3x9 So, 234567 is not a prime number because it is divisible by 3.
13
The answer is 39. 3+9=12, 3x9=27. 12+27=39.
The number is 23.
2014 ( The sum of the digits = 7, a prime number )
It is: 59
what number is prime to 40 29 - it's a prime number (divisible only by 1 and itself) and if you sum the two digits 2 + 9 = 11
59
I think it will be 17. The sum of digits is 8, which is the cube of 2.
11
31.
If you multiply two prime numbers, the product (result) will be a composite number, not a prime number. A prime number has exactly two factors, 1 and itself. The product of two prime numbers will have those two numbers as factors, as well. The sum of two prime numbers might be prime if one of those two numbers is 2, the only even prime number, but otherwise it will not be a prime because two odd numbers will have an even sum, which means it is divisible by 2. Examples: 2 + 3 = 5 (prime) 3 + 7 = 10 (not prime) 13 + 17 = 30 (not prime) If you multiply two prime numbers, the sum of the digits of the product might or might not be prime. Examples: 2 x 7 = 14, sum of digits is 5 (prime) 2 x 11 = 22, sum of digits is 4 (not prime) 3 x 5 = 15, sum of digits is 6 (not prime) 3 x 7 = 21, sum of digits is 3 (prime) 5 x 7 = 35, sum of digits is 8 (prime)
83