28578005 has 4 divisors (see below), whose sum is σ = 34293612. Its totient is φ = 22862400.

The previous prime is 28577987. The next prime is 28578019. The reversal of 28578005 is 50087582.

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 20133169 + 8444836 = 4487^2 + 2906^2 .

It is a de Polignac number, because none of the positive numbers 2^k-28578005 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2857796 + ... + 2857805.

It is an arithmetic number, because the mean of its divisors is an integer number (8573403).

Almost surely, 2^28578005 is an apocalyptic number.

It is an amenable number.

28578005 is a deficient number, since it is larger than the sum of its proper divisors (5715607).

28578005 is an equidigital number, since it uses as much as digits as its factorization.

28578005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5715606.

The product of its (nonzero) digits is 22400, while the sum is 35.

The square root of 28578005 is about 5345.8399714170. The cubic root of 28578005 is about 305.7341625876.

The spelling of 28578005 in words is "twenty-eight million, five hundred seventy-eight thousand, five".