12090391 has 4 divisors (see below), whose sum is σ = 12144832. Its totient is φ = 12035952.

The previous prime is 12090343. The next prime is 12090409. The reversal of 12090391 is 19309021.

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 12090391 - 2⁷ = 12090263 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 (12090301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26886 + ... + 27331.

It is an arithmetic number, because the mean of its divisors is an integer number (3036208).

Almost surely, 2^12090391 is an apocalyptic number.

12090391 is a deficient number, since it is larger than the sum of its proper divisors (54441).

12090391 is an equidigital number, since it uses as much as digits as its factorization.

12090391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54440.

The product of its (nonzero) digits is 486, while the sum is 25.

The square root of 12090391 is about 3477.1239552251. The cubic root of 12090391 is about 229.5162548629.

The spelling of 12090391 in words is "twelve million, ninety thousand, three hundred ninety-one".