28679509 has 2 divisors, whose sum is σ = 28679510. Its totient is φ = 28679508.

The previous prime is 28679507. The next prime is 28679543. The reversal of 28679509 is 90597682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26780625 + 1898884 = 5175^2 + 1378^2 .

It is a cyclic number.

It is not a de Polignac number, because 28679509 - 2¹ = 28679507 is a prime.

Together with 28679507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28679507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14339754 + 14339755.

It is an arithmetic number, because the mean of its divisors is an integer number (14339755).

Almost surely, 2^28679509 is an apocalyptic number.

It is an amenable number.

28679509 is a deficient number, since it is larger than the sum of its proper divisors (1).

28679509 is an equidigital number, since it uses as much as digits as its factorization.

28679509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 46.

The square root of 28679509 is about 5355.3252935746. The cubic root of 28679509 is about 306.0957060339.

The spelling of 28679509 in words is "twenty-eight million, six hundred seventy-nine thousand, five hundred nine".