28258209 has 24 divisors (see below), whose sum is σ = 48260160. Its totient is φ = 15589728.

The previous prime is 28258207. The next prime is 28258231. The reversal of 28258209 is 90285282.

28258209 is nontrivially palindromic in base 16.

It is not a de Polignac number, because 28258209 - 2¹ = 28258207 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28258207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5907 + ... + 9560.

It is an arithmetic number, because the mean of its divisors is an integer number (2010840).

Almost surely, 2^28258209 is an apocalyptic number.

28258209 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28258209 is a deficient number, since it is larger than the sum of its proper divisors (20001951).

28258209 is a wasteful number, since it uses less digits than its factorization.

28258209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15509 (or 15506 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 28258209 is about 5315.8450880363. The cubic root of 28258209 is about 304.5894646807.

The spelling of 28258209 in words is "twenty-eight million, two hundred fifty-eight thousand, two hundred nine".