12656891 has 8 divisors (see below), whose sum is σ = 14432544. Its totient is φ = 10995840.

The previous prime is 12656887. The next prime is 12656899. The reversal of 12656891 is 19865621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12656891 - 2² = 12656887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12656899) 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 in 7 ways as a sum of consecutive naturals, for example, 28415 + ... + 28856.

It is an arithmetic number, because the mean of its divisors is an integer number (1804068).

Almost surely, 2^12656891 is an apocalyptic number.

12656891 is a deficient number, since it is larger than the sum of its proper divisors (1775653).

12656891 is a wasteful number, since it uses less digits than its factorization.

12656891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57301.

The product of its digits is 25920, while the sum is 38.

The square root of 12656891 is about 3557.6524563257. The cubic root of 12656891 is about 233.0463721735.

The spelling of 12656891 in words is "twelve million, six hundred fifty-six thousand, eight hundred ninety-one".