12556665 has 24 divisors (see below), whose sum is σ = 23744448. Its totient is φ = 6087840.

The previous prime is 12556639. The next prime is 12556669. The reversal of 12556665 is 56665521.

It is a happy number.

It is not a de Polignac number, because 12556665 - 2⁹ = 12556153 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12556669) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12189 + ... + 13178.

It is an arithmetic number, because the mean of its divisors is an integer number (989352).

Almost surely, 2^12556665 is an apocalyptic number.

12556665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12556665 is a deficient number, since it is larger than the sum of its proper divisors (11187783).

12556665 is a wasteful number, since it uses less digits than its factorization.

12556665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25389 (or 25386 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 12556665 is about 3543.5384857512. The cubic root of 12556665 is about 232.4296006073.

The spelling of 12556665 in words is "twelve million, five hundred fifty-six thousand, six hundred sixty-five".