The crisp new dollar bill that I have just taken from my wallet bears the serial number 24598176. It’s easy to tell that the number is exactly divisible by 2 but not by 5. Is it divisible by 3? by 4?

Prime numbers have fascinated mathematicians for centuries, yet many students find them intimidating. Whether you're preparing for competitive exams like JEE, solving number theory problems, or simply ...

Do you have a preference for odd or even numbers? Marissa Mayer, the CEO of Yahoo, does: "I really like even numbers, and I like heavily divisible numbers," she says in the latest Vogue. "Twelve is my ...

Three and five are prime numbers - that is, they are divisible only by one and by themselves. So are five and seven. And 11 and 13. And for each of these pairs of prime numbers, the difference is two.