1285209 has 12 divisors (see below), whose sum is σ = 1887652. Its totient is φ = 842400.

The previous prime is 1285199. The next prime is 1285213. The reversal of 1285209 is 9025821.

It can be written as a sum of positive squares in 2 ways, for example, as 363609 + 921600 = 603^2 + 960^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1285209 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1285259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 622 + ... + 1719.

2^1285209 is an apocalyptic number.

It is an amenable number.

1285209 is a deficient number, since it is larger than the sum of its proper divisors (602443).

1285209 is a wasteful number, since it uses less digits than its factorization.

1285209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2408 (or 2405 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1285209 is about 1133.6705870755. The cubic root of 1285209 is about 108.7237907509.

The spelling of 1285209 in words is "one million, two hundred eighty-five thousand, two hundred nine".