28324009 has 6 divisors (see below), whose sum is σ = 32948394. Its totient is φ = 24277680.

The previous prime is 28323979. The next prime is 28324013. The reversal of 28324009 is 90042382.

It can be written as a sum of positive squares in only one way, i.e., 28302400 + 21609 = 5320^2 + 147^2 .

It is not a de Polignac number, because 28324009 - 2⁷ = 28323881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28324019) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 288972 + ... + 289069.

It is an arithmetic number, because the mean of its divisors is an integer number (5491399).

Almost surely, 2^28324009 is an apocalyptic number.

It is an amenable number.

28324009 is a deficient number, since it is larger than the sum of its proper divisors (4624385).

28324009 is an equidigital number, since it uses as much as digits as its factorization.

28324009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 578055 (or 578048 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 28324009 is about 5322.0305335464. The cubic root of 28324009 is about 304.8256963396.

The spelling of 28324009 in words is "twenty-eight million, three hundred twenty-four thousand, nine".