12681891 has 12 divisors (see below), whose sum is σ = 18388032. Its totient is φ = 8422416.

The previous prime is 12681871. The next prime is 12681931. The reversal of 12681891 is 19818621.

It is not a de Polignac number, because 12681891 - 2⁵ = 12681859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12681871) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 51 + ... + 5036.

It is an arithmetic number, because the mean of its divisors is an integer number (1532336).

Almost surely, 2^12681891 is an apocalyptic number.

12681891 is a deficient number, since it is larger than the sum of its proper divisors (5706141).

12681891 is a wasteful number, since it uses less digits than its factorization.

12681891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5370 (or 5367 counting only the distinct ones).

The product of its digits is 6912, while the sum is 36.

The square root of 12681891 is about 3561.1642759075. The cubic root of 12681891 is about 233.1997096598.

The spelling of 12681891 in words is "twelve million, six hundred eighty-one thousand, eight hundred ninety-one".