12865891 has 4 divisors (see below), whose sum is σ = 12882384. Its totient is φ = 12849400.

The previous prime is 12865883. The next prime is 12865927. The reversal of 12865891 is 19856821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12865891 - 2³ = 12865883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12865871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7015 + ... + 8656.

It is an arithmetic number, because the mean of its divisors is an integer number (3220596).

Almost surely, 2^12865891 is an apocalyptic number.

12865891 is a deficient number, since it is larger than the sum of its proper divisors (16493).

12865891 is an equidigital number, since it uses as much as digits as its factorization.

12865891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16492.

The product of its digits is 34560, while the sum is 40.

The square root of 12865891 is about 3586.9054908096. The cubic root of 12865891 is about 234.3221207163.

The spelling of 12865891 in words is "twelve million, eight hundred sixty-five thousand, eight hundred ninety-one".