28394909 has 8 divisors (see below), whose sum is σ = 29548800. Its totient is φ = 27264016.

The previous prime is 28394897. The next prime is 28394917. The reversal of 28394909 is 90949382.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28394909 - 2⁴ = 28394893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28394909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28394929) 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 in 7 ways as a sum of consecutive naturals, for example, 3209 + ... + 8190.

It is an arithmetic number, because the mean of its divisors is an integer number (3693600).

Almost surely, 2^28394909 is an apocalyptic number.

It is an amenable number.

28394909 is a deficient number, since it is larger than the sum of its proper divisors (1153891).

28394909 is a wasteful number, since it uses less digits than its factorization.

28394909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11499.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 28394909 is about 5328.6873618181. The cubic root of 28394909 is about 305.0798286072.

The spelling of 28394909 in words is "twenty-eight million, three hundred ninety-four thousand, nine hundred nine".