1725

1725 = 3 x 5 x 5 x 23.

1725 is a structured deltoidal hexacontahedral number (A100166).

1725 is 122331 in base 4.

1725 is the sum of odd numbers in the range 340 to 349 (A053742).

1725 is the number of numbers with five decimal digits and digit sum 13 (A090580).

1725 is the upper of a pair of consecutive happy numbers (A035503).

Source: What's Special About This Number?