12665671 has 2 divisors, whose sum is σ = 12665672. Its totient is φ = 12665670.

The previous prime is 12665669. The next prime is 12665677. The reversal of 12665671 is 17656621.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12665671 - 2¹ = 12665669 is a prime.

Together with 12665669, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12665677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6332835 + 6332836.

It is an arithmetic number, because the mean of its divisors is an integer number (6332836).

Almost surely, 2^12665671 is an apocalyptic number.

12665671 is a deficient number, since it is larger than the sum of its proper divisors (1).

12665671 is an equidigital number, since it uses as much as digits as its factorization.

12665671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 34.

The square root of 12665671 is about 3558.8862021706. The cubic root of 12665671 is about 233.1002472839.

The spelling of 12665671 in words is "twelve million, six hundred sixty-five thousand, six hundred seventy-one".