12521009 has 2 divisors, whose sum is σ = 12521010. Its totient is φ = 12521008.

The previous prime is 12520999. The next prime is 12521017. The reversal of 12521009 is 90012521.

12521009 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12271009 + 250000 = 3503^2 + 500^2 .

It is a cyclic number.

It is not a de Polignac number, because 12521009 - 2¹⁶ = 12455473 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12521099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6260504 + 6260505.

It is an arithmetic number, because the mean of its divisors is an integer number (6260505).

Almost surely, 2^12521009 is an apocalyptic number.

It is an amenable number.

12521009 is a deficient number, since it is larger than the sum of its proper divisors (1).

12521009 is an equidigital number, since it uses as much as digits as its factorization.

12521009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 12521009 is about 3538.5037798482. The cubic root of 12521009 is about 232.2093890925.

The spelling of 12521009 in words is "twelve million, five hundred twenty-one thousand, nine".