1280009 has 4 divisors (see below), whose sum is σ = 1284816. Its totient is φ = 1275204.

The previous prime is 1279997. The next prime is 1280023. The reversal of 1280009 is 9000821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1280009 - 2⁸ = 1279753 is a prime.

It is a super-3 number, since 3×1280009³ = 6291588711333122187, which contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1280309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1979 + ... + 2544.

It is an arithmetic number, because the mean of its divisors is an integer number (321204).

2^1280009 is an apocalyptic number.

It is an amenable number.

1280009 is a deficient number, since it is larger than the sum of its proper divisors (4807).

1280009 is an equidigital number, since it uses as much as digits as its factorization.

1280009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4806.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 1280009 is about 1131.3748273671. The cubic root of 1280009 is about 108.5769591399.

The spelling of 1280009 in words is "one million, two hundred eighty thousand, nine".