306

306 = 2 x 3² x 17.

3*306 + 0*306 + 6*306 - 1 is a prime number.

306 is the number of five-digit triangular numbers.

306 is the sum of four consecutive primes: 71 + 73 + 79 + 83 = 306.

306 has a representation as a sum of two squares: 306 = 9² + 15².

306 is the telephone area code for Saskatchewan, Canada.

Source: Prime Curios!