28657009 has 2 divisors, whose sum is σ = 28657010. Its totient is φ = 28657008.

The previous prime is 28657003. The next prime is 28657037. The reversal of 28657009 is 90075682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28090000 + 567009 = 5300^2 + 753^2 .

It is a cyclic number.

It is not a de Polignac number, because 28657009 - 2¹⁹ = 28132721 is a prime.

It is not a weakly prime, because it can be changed into another prime (28657003) 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, 14328504 + 14328505.

It is an arithmetic number, because the mean of its divisors is an integer number (14328505).

Almost surely, 2^28657009 is an apocalyptic number.

It is an amenable number.

28657009 is a deficient number, since it is larger than the sum of its proper divisors (1).

28657009 is an equidigital number, since it uses as much as digits as its factorization.

28657009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 28657009 is about 5353.2241686670. The cubic root of 28657009 is about 306.0156377729.

The spelling of 28657009 in words is "twenty-eight million, six hundred fifty-seven thousand, nine".