Primes which differ by 2 are called 

GCD of 36, 48 and 64 is 

Numbers which are completely divisible by 2 are 

GCD of 45 and 63 is 

Sum of the first seven odd numbers is 

1000 - 452 is ________ number. 

Product of two numbers = _______  x  GCD

Which of the following  are twin prime numbers. 

GCD of any two relatively prime numbers is 

What these numbers 16 = 2 x 2 x 2 x 2 ; 15 = 3 x 5 denote?