12985891 has 2 divisors, whose sum is σ = 12985892. Its totient is φ = 12985890.

The previous prime is 12985867. The next prime is 12985919. The reversal of 12985891 is 19858921.

It is a weak prime.

It is an emirp because it is prime and its reverse (19858921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12985891 - 2¹¹ = 12983843 is a prime.

It is not a weakly prime, because it can be changed into another prime (12985801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6492945 + 6492946.

It is an arithmetic number, because the mean of its divisors is an integer number (6492946).

Almost surely, 2^12985891 is an apocalyptic number.

12985891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12985891 is an equidigital number, since it uses as much as digits as its factorization.

12985891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 43.

The square root of 12985891 is about 3603.5941780395. The cubic root of 12985891 is about 235.0483739258.

It can be divided in two parts, 1 and 2985891, that added together give a palindrome (2985892).

The spelling of 12985891 in words is "twelve million, nine hundred eighty-five thousand, eight hundred ninety-one".