28726809 has 8 divisors (see below), whose sum is σ = 38327520. Its totient is φ = 19138656.

The previous prime is 28726807. The next prime is 28726829. The reversal of 28726809 is 90862782.

It is a happy number.

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

It is not a de Polignac number, because 28726809 - 2¹ = 28726807 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (28726807) 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, 6022 + ... + 9680.

It is an arithmetic number, because the mean of its divisors is an integer number (4790940).

Almost surely, 2^28726809 is an apocalyptic number.

It is an amenable number.

28726809 is a deficient number, since it is larger than the sum of its proper divisors (9600711).

28726809 is a wasteful number, since it uses less digits than its factorization.

28726809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6279.

The product of its (nonzero) digits is 96768, while the sum is 42.

The square root of 28726809 is about 5359.7396391989. The cubic root of 28726809 is about 306.2638908596.

The spelling of 28726809 in words is "twenty-eight million, seven hundred twenty-six thousand, eight hundred nine".