12866865 has 32 divisors (see below), whose sum is σ = 23241600. Its totient is φ = 6021120.

The previous prime is 12866851. The next prime is 12866869. The reversal of 12866865 is 56866821.

It is not a de Polignac number, because 12866865 - 2⁶ = 12866801 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12866869) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3441 + ... + 6129.

It is an arithmetic number, because the mean of its divisors is an integer number (726300).

Almost surely, 2^12866865 is an apocalyptic number.

12866865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12866865 is a deficient number, since it is larger than the sum of its proper divisors (10374735).

12866865 is a wasteful number, since it uses less digits than its factorization.

12866865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2737.

The product of its digits is 138240, while the sum is 42.

The square root of 12866865 is about 3587.0412598686. The cubic root of 12866865 is about 234.3280336113.

It can be divided in two parts, 12866 and 865, that added together give a palindrome (13731).

The spelling of 12866865 in words is "twelve million, eight hundred sixty-six thousand, eight hundred sixty-five".