12661589 has 2 divisors, whose sum is σ = 12661590. Its totient is φ = 12661588.

The previous prime is 12661499. The next prime is 12661591. The reversal of 12661589 is 98516621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7896100 + 4765489 = 2810^2 + 2183^2 .

It is a cyclic number.

It is not a de Polignac number, because 12661589 - 2¹⁶ = 12596053 is a prime.

Together with 12661591, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p₈₂₈₅₆₉ and since 12661589 and 828569 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12660589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6330794 + 6330795.

It is an arithmetic number, because the mean of its divisors is an integer number (6330795).

Almost surely, 2^12661589 is an apocalyptic number.

It is an amenable number.

12661589 is a deficient number, since it is larger than the sum of its proper divisors (1).

12661589 is an equidigital number, since it uses as much as digits as its factorization.

12661589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 38.

The square root of 12661589 is about 3558.3126619228. The cubic root of 12661589 is about 233.0752027508.

The spelling of 12661589 in words is "twelve million, six hundred sixty-one thousand, five hundred eighty-nine".