12581665 has 16 divisors (see below), whose sum is σ = 15846912. Its totient is φ = 9578304.

The previous prime is 12581659. The next prime is 12581689. The reversal of 12581665 is 56618521.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 12581665 - 2⁷ = 12581537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12581665.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7972 + ... + 9418.

It is an arithmetic number, because the mean of its divisors is an integer number (990432).

Almost surely, 2^12581665 is an apocalyptic number.

It is an amenable number.

12581665 is a deficient number, since it is larger than the sum of its proper divisors (3265247).

12581665 is a wasteful number, since it uses less digits than its factorization.

12581665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1536.

The product of its digits is 14400, while the sum is 34.

The square root of 12581665 is about 3547.0642790905. The cubic root of 12581665 is about 232.5837521523.

The spelling of 12581665 in words is "twelve million, five hundred eighty-one thousand, six hundred sixty-five".