539

539 = 7 x 7 x 11.

539 is the number of multigraphs with five vertices and nine edges.

539 is 2255 in base 6 and 1400 in base 7.

539 is the sum of two distinct positive cubes (A024670): 539 = 8³ + 3³.

Inserting the digit 9 between adjacent digits of 539 makes a prime (A050719): 59399.

539 is the sum of 11 consecutive primes (A127338): 539 = 29 + 31 + 37 + 41 + 43 + 47 + 53 + 59 + 61 + 67 + 71.

Source: What's Special About This Number?