28835509 has 4 divisors (see below), whose sum is σ = 28907820. Its totient is φ = 28763200.

The previous prime is 28835503. The next prime is 28835539. The reversal of 28835509 is 90553882.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24039409 + 4796100 = 4903^2 + 2190^2 .

It is a cyclic number.

It is not a de Polignac number, because 28835509 - 2³ = 28835501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28835501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35554 + ... + 36355.

It is an arithmetic number, because the mean of its divisors is an integer number (7226955).

Almost surely, 2^28835509 is an apocalyptic number.

It is an amenable number.

28835509 is a deficient number, since it is larger than the sum of its proper divisors (72311).

28835509 is an equidigital number, since it uses as much as digits as its factorization.

28835509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72310.

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 28835509 is about 5369.8704826094. The cubic root of 28835509 is about 306.6496975225.

The spelling of 28835509 in words is "twenty-eight million, eight hundred thirty-five thousand, five hundred nine".