1785

1785 = 3 x 5 x 7 x 17.

1785 is a multiple of 7 such that its digit sum is divisible by 7 (A216994).

1785 is a square pyramidal number (A000330). It is also a pentadecagonal number (A051867).

1785 is palindromic in base 5: 123321.

1785 is the sum of five positive fifth powers (A003350).

1785 divides 13⁴ - 1.

Source: OEIS