12312191 has 2 divisors, whose sum is σ = 12312192. Its totient is φ = 12312190.

The previous prime is 12312173. The next prime is 12312193. The reversal of 12312191 is 19121321.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12312191 is a prime.

Together with 12312193, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12312193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6156095 + 6156096.

It is an arithmetic number, because the mean of its divisors is an integer number (6156096).

Almost surely, 2^12312191 is an apocalyptic number.

12312191 is a deficient number, since it is larger than the sum of its proper divisors (1).

12312191 is an equidigital number, since it uses as much as digits as its factorization.

12312191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108, while the sum is 20.

The square root of 12312191 is about 3508.8731809514. The cubic root of 12312191 is about 230.9112619311.

The spelling of 12312191 in words is "twelve million, three hundred twelve thousand, one hundred ninety-one".