12528409 has 2 divisors, whose sum is σ = 12528410. Its totient is φ = 12528408.

The previous prime is 12528407. The next prime is 12528413. The reversal of 12528409 is 90482521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11256025 + 1272384 = 3355^2 + 1128^2 .

It is a cyclic number.

It is not a de Polignac number, because 12528409 - 2¹ = 12528407 is a prime.

It is a super-2 number, since 2×12528409² = 313922064142562, which contains 22 as substring.

Together with 12528407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12528403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6264204 + 6264205.

It is an arithmetic number, because the mean of its divisors is an integer number (6264205).

Almost surely, 2^12528409 is an apocalyptic number.

It is an amenable number.

12528409 is a deficient number, since it is larger than the sum of its proper divisors (1).

12528409 is an equidigital number, since it uses as much as digits as its factorization.

12528409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 12528409 is about 3539.5492650901. The cubic root of 12528409 is about 232.2551258504.

The spelling of 12528409 in words is "twelve million, five hundred twenty-eight thousand, four hundred nine".