12871891 has 2 divisors, whose sum is σ = 12871892. Its totient is φ = 12871890.

The previous prime is 12871877. The next prime is 12871933. The reversal of 12871891 is 19817821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12871891 - 2⁷ = 12871763 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12871891.

It is not a weakly prime, because it can be changed into another prime (12871811) 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 as a sum of consecutive naturals, namely, 6435945 + 6435946.

It is an arithmetic number, because the mean of its divisors is an integer number (6435946).

Almost surely, 2^12871891 is an apocalyptic number.

12871891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12871891 is an equidigital number, since it uses as much as digits as its factorization.

12871891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 37.

The square root of 12871891 is about 3587.7417688568. The cubic root of 12871891 is about 234.3585403789.

The spelling of 12871891 in words is "twelve million, eight hundred seventy-one thousand, eight hundred ninety-one".