1501

1501 = 19 x 79.

1501 is palindromic in base 2 (binary): 10111011101. It is 535 in base 17.

1501 is a centered pentagonal number (A005891).

1501 is the smallest number representable as the sum of three triangular numbers in exactly 33 ways (A061262).

1501 is a divisor of 56⁶ - 1.

Source: On-Line Encyclopedia of Integer Sequences