1425

1425 = 3 x 5 x 5 x 19.

1425 is 10110010001 in base 2 (binary). It is a self-descriptive number in base 5: 21200.

The sum of the digits of 1425 is equal to the number of divisors of 1425 (1, 3, 5, 15, 19, 25, 57, 75, 95, 285, 475, 1425): 1 + 4 + 2 + 5 = 12 (A057531 and A057532).

1425 is the sum of the first 31 semiprimes (A062198).

Every digit occurs at least once in 1425⁴: 4,123,437,890,625 (A121321).

Source: On-Line Encyclopedia of Integer Sequences