12857891 has 2 divisors, whose sum is σ = 12857892. Its totient is φ = 12857890.

The previous prime is 12857881. The next prime is 12857893. The reversal of 12857891 is 19875821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12857891 - 2⁶ = 12857827 is a prime.

Together with 12857893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12857893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6428945 + 6428946.

It is an arithmetic number, because the mean of its divisors is an integer number (6428946).

Almost surely, 2^12857891 is an apocalyptic number.

12857891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12857891 is an equidigital number, since it uses as much as digits as its factorization.

12857891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 41.

The square root of 12857891 is about 3585.7901500227. The cubic root of 12857891 is about 234.2735435485.

The spelling of 12857891 in words is "twelve million, eight hundred fifty-seven thousand, eight hundred ninety-one".