12391491 has 8 divisors (see below), whose sum is σ = 18882304. Its totient is φ = 7080840.

The previous prime is 12391481. The next prime is 12391493. The reversal of 12391491 is 19419321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12391491 - 2⁶ = 12391427 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12391493) 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 7 ways as a sum of consecutive naturals, for example, 295015 + ... + 295056.

It is an arithmetic number, because the mean of its divisors is an integer number (2360288).

Almost surely, 2^12391491 is an apocalyptic number.

12391491 is a deficient number, since it is larger than the sum of its proper divisors (6490813).

12391491 is an equidigital number, since it uses as much as digits as its factorization.

12391491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 590081.

The product of its digits is 1944, while the sum is 30.

The square root of 12391491 is about 3520.1549681797. The cubic root of 12391491 is about 231.4059502243.

The spelling of 12391491 in words is "twelve million, three hundred ninety-one thousand, four hundred ninety-one".