28499209 has 2 divisors, whose sum is σ = 28499210. Its totient is φ = 28499208.

The previous prime is 28499203. The next prime is 28499227. The reversal of 28499209 is 90299482.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15015625 + 13483584 = 3875^2 + 3672^2 .

It is a cyclic number.

It is not a de Polignac number, because 28499209 - 2³ = 28499201 is a prime.

It is not a weakly prime, because it can be changed into another prime (28499201) 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, 14249604 + 14249605.

It is an arithmetic number, because the mean of its divisors is an integer number (14249605).

Almost surely, 2^28499209 is an apocalyptic number.

It is an amenable number.

28499209 is a deficient number, since it is larger than the sum of its proper divisors (1).

28499209 is an equidigital number, since it uses as much as digits as its factorization.

28499209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 28499209 is about 5338.4650415639. The cubic root of 28499209 is about 305.4529112762.

The spelling of 28499209 in words is "twenty-eight million, four hundred ninety-nine thousand, two hundred nine".