1330391 has 4 divisors (see below), whose sum is σ = 1353000. Its totient is φ = 1307784.

The previous prime is 1330337. The next prime is 1330393. The reversal of 1330391 is 1930331.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1330391 - 2¹⁸ = 1068247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1330393) 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 3 ways as a sum of consecutive naturals, for example, 11216 + ... + 11333.

It is an arithmetic number, because the mean of its divisors is an integer number (338250).

2^1330391 is an apocalyptic number.

1330391 is a deficient number, since it is larger than the sum of its proper divisors (22609).

1330391 is an equidigital number, since it uses as much as digits as its factorization.

1330391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22608.

The product of its (nonzero) digits is 243, while the sum is 20.

The square root of 1330391 is about 1153.4257670089. The cubic root of 1330391 is about 109.9832205811.

The spelling of 1330391 in words is "one million, three hundred thirty thousand, three hundred ninety-one".