11 (number) "ùndici" (but in Spanish and Portuguese, 16, and in French, 17 is the first compound number), Chinese 十一 "shí yī", Korean 열한 "yeol han". 11 is a prime number. It is the smallest two-digit prime number in the decimal base. The next prime is 13, with which it comprises a twin prime. If a number is divisible by 11, reversing its digits will result in another multiple of 11. As long as no two adjacent digits of a number added together exceed 9, then multiplying the number by 11, reversing the digits of the product, and dividing that new number
17 (number) 17 (number) 17 (seventeen) is the natural number following 16 and preceding 18. It is a prime number. In English speech, the numbers 17 and 70 are sometimes confused, as they sound very similar. The number 17 has wide significance in pure mathematics, as well as in applied sciences, law, music, religion, sports, and other cultural phenomena. Seventeen is the sum of the first four prime numbers. Seventeen is the seventh prime number. The next prime is nineteen, with which it forms a twin prime. Seventeen is a permutable prime and a supersingular prime. Seventeen is the third Fermat prime,