12987409 has 2 divisors, whose sum is σ = 12987410. Its totient is φ = 12987408.

The previous prime is 12987397. The next prime is 12987413. The reversal of 12987409 is 90478921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11289600 + 1697809 = 3360^2 + 1303^2 .

It is a cyclic number.

It is not a de Polignac number, because 12987409 - 2¹¹ = 12985361 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12987509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6493704 + 6493705.

It is an arithmetic number, because the mean of its divisors is an integer number (6493705).

Almost surely, 2^12987409 is an apocalyptic number.

It is an amenable number.

12987409 is a deficient number, since it is larger than the sum of its proper divisors (1).

12987409 is an equidigital number, since it uses as much as digits as its factorization.

12987409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 12987409 is about 3603.8047949355. The cubic root of 12987409 is about 235.0575323150.

The spelling of 12987409 in words is "twelve million, nine hundred eighty-seven thousand, four hundred nine".