28422809 has 8 divisors (see below), whose sum is σ = 28752840. Its totient is φ = 28094976.

The previous prime is 28422763. The next prime is 28422811. The reversal of 28422809 is 90822482.

It can be written as a sum of positive squares in 4 ways, for example, as 120409 + 28302400 = 347^2 + 5320^2 .

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 28422809 - 2²⁴ = 11645593 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28422829) 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, 41897 + ... + 42569.

It is an arithmetic number, because the mean of its divisors is an integer number (3594105).

Almost surely, 2^28422809 is an apocalyptic number.

It is an amenable number.

28422809 is a deficient number, since it is larger than the sum of its proper divisors (330031).

28422809 is a wasteful number, since it uses less digits than its factorization.

28422809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099.

The product of its (nonzero) digits is 18432, while the sum is 35.

The square root of 28422809 is about 5331.3046245736. The cubic root of 28422809 is about 305.1797167121.

The spelling of 28422809 in words is "twenty-eight million, four hundred twenty-two thousand, eight hundred nine".