28580665 has 4 divisors (see below), whose sum is σ = 34296804. Its totient is φ = 22864528.

The previous prime is 28580641. The next prime is 28580683. The reversal of 28580665 is 56608582.

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 6827769 + 21752896 = 2613^2 + 4664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28580665 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2858062 + ... + 2858071.

It is an arithmetic number, because the mean of its divisors is an integer number (8574201).

Almost surely, 2^28580665 is an apocalyptic number.

It is an amenable number.

28580665 is a deficient number, since it is larger than the sum of its proper divisors (5716139).

28580665 is an equidigital number, since it uses as much as digits as its factorization.

28580665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5716138.

The product of its (nonzero) digits is 115200, while the sum is 40.

The square root of 28580665 is about 5346.0887572131. The cubic root of 28580665 is about 305.7436480601.

The spelling of 28580665 in words is "twenty-eight million, five hundred eighty thousand, six hundred sixty-five".