12666389 has 2 divisors, whose sum is σ = 12666390. Its totient is φ = 12666388.

The previous prime is 12666371. The next prime is 12666413. The reversal of 12666389 is 98366621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11847364 + 819025 = 3442^2 + 905^2 .

It is an emirp because it is prime and its reverse (98366621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12666389 - 2⁸ = 12666133 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12663389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6333194 + 6333195.

It is an arithmetic number, because the mean of its divisors is an integer number (6333195).

Almost surely, 2^12666389 is an apocalyptic number.

It is an amenable number.

12666389 is a deficient number, since it is larger than the sum of its proper divisors (1).

12666389 is an equidigital number, since it uses as much as digits as its factorization.

12666389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 41.

The square root of 12666389 is about 3558.9870749976. The cubic root of 12666389 is about 233.1046519147.

The spelling of 12666389 in words is "twelve million, six hundred sixty-six thousand, three hundred eighty-nine".