12665431 has 4 divisors (see below), whose sum is σ = 13102200. Its totient is φ = 12228664.

The previous prime is 12665423. The next prime is 12665441. The reversal of 12665431 is 13456621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13456621 = 3299 ⋅4079.

It is a cyclic number.

It is not a de Polignac number, because 12665431 - 2³ = 12665423 is a prime.

It is a super-2 number, since 2×12665431² = 320826284831522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 12665431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12665441) 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, 218341 + ... + 218398.

It is an arithmetic number, because the mean of its divisors is an integer number (3275550).

Almost surely, 2^12665431 is an apocalyptic number.

12665431 is a deficient number, since it is larger than the sum of its proper divisors (436769).

12665431 is an equidigital number, since it uses as much as digits as its factorization.

12665431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436768.

The product of its digits is 4320, while the sum is 28.

The square root of 12665431 is about 3558.8524835964. The cubic root of 12665431 is about 233.0987749467.

The spelling of 12665431 in words is "twelve million, six hundred sixty-five thousand, four hundred thirty-one".