1328009 has 4 divisors (see below), whose sum is σ = 1370880. Its totient is φ = 1285140.

The previous prime is 1328003. The next prime is 1328017. The reversal of 1328009 is 9008231.

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 a de Polignac number, because none of the positive numbers 2^k-1328009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1328003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21389 + ... + 21450.

It is an arithmetic number, because the mean of its divisors is an integer number (342720).

2^1328009 is an apocalyptic number.

It is an amenable number.

1328009 is a deficient number, since it is larger than the sum of its proper divisors (42871).

1328009 is an equidigital number, since it uses as much as digits as its factorization.

1328009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42870.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 1328009 is about 1152.3927281964. The cubic root of 1328009 is about 109.9175415085.

The spelling of 1328009 in words is "one million, three hundred twenty-eight thousand, nine".