28290985 has 8 divisors (see below), whose sum is σ = 33977736. Its totient is φ = 22613760.

The previous prime is 28290967. The next prime is 28290991. The reversal of 28290985 is 58909282.

It can be written as a sum of positive squares in 4 ways, for example, as 12033961 + 16257024 = 3469^2 + 4032^2 .

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

It is not a de Polignac number, because 28290985 - 2⁵ = 28290953 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 (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10497 + ... + 12913.

It is an arithmetic number, because the mean of its divisors is an integer number (4247217).

Almost surely, 2^28290985 is an apocalyptic number.

It is an amenable number.

28290985 is a deficient number, since it is larger than the sum of its proper divisors (5686751).

28290985 is a wasteful number, since it uses less digits than its factorization.

28290985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4763.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 28290985 is about 5318.9270534573. The cubic root of 28290985 is about 304.7071811175.

The spelling of 28290985 in words is "twenty-eight million, two hundred ninety thousand, nine hundred eighty-five".