12665985 has 16 divisors (see below), whose sum is σ = 21147264. Its totient is φ = 6461312.

The previous prime is 12665959. The next prime is 12665987. The reversal of 12665985 is 58956621.

It is a cyclic number.

It is not a de Polignac number, because 12665985 - 2¹⁰ = 12664961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12665987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18012 + ... + 18701.

It is an arithmetic number, because the mean of its divisors is an integer number (1321704).

Almost surely, 2^12665985 is an apocalyptic number.

12665985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12665985 is a deficient number, since it is larger than the sum of its proper divisors (8481279).

12665985 is a wasteful number, since it uses less digits than its factorization.

12665985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36744.

The product of its digits is 129600, while the sum is 42.

The square root of 12665985 is about 3558.9303168227. The cubic root of 12665985 is about 233.1021735635.

The spelling of 12665985 in words is "twelve million, six hundred sixty-five thousand, nine hundred eighty-five".