1321009 has 4 divisors (see below), whose sum is σ = 1323520. Its totient is φ = 1318500.

The previous prime is 1321007. The next prime is 1321031. The reversal of 1321009 is 9001231.

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 1321009 - 2¹ = 1321007 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320983 and 1321001.

It is not an unprimeable number, because it can be changed into a prime (1321007) 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, 129 + ... + 1630.

It is an arithmetic number, because the mean of its divisors is an integer number (330880).

2^1321009 is an apocalyptic number.

It is an amenable number.

1321009 is a deficient number, since it is larger than the sum of its proper divisors (2511).

1321009 is an equidigital number, since it uses as much as digits as its factorization.

1321009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2510.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 1321009 is about 1149.3515563134. The cubic root of 1321009 is about 109.7240742826.

The spelling of 1321009 in words is "one million, three hundred twenty-one thousand, nine".