Randomly scramble the digits 0, 1, 2, 3, 4, 5 and 6 to form a seven-digit number (or a six-digit number if the leading digit is 0). Rank the following events in order ...

Find one million consecutive positive numbers, none of which are prime. Ancient math tells us that prime numbers (2, 3, 5, 7, 11, ...,), which have no factors except for 1 and themselves, go on ...

The number 1 is not considered a prime number because it has only 1 positive divisor. Some prime numbers form “twin primes,” like 11 and 13 or 17 and 19. These pairs differ by exactly two. Large prime ...