28286705 has 8 divisors (see below), whose sum is σ = 34077672. Its totient is φ = 22540288.

The previous prime is 28286677. The next prime is 28286717. The reversal of 28286705 is 50768282.

It can be written as a sum of positive squares in 4 ways, for example, as 13162384 + 15124321 = 3628^2 + 3889^2 .

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 28286705 - 2⁶ = 28286641 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, 9722 + ... + 12291.

It is an arithmetic number, because the mean of its divisors is an integer number (4259709).

Almost surely, 2^28286705 is an apocalyptic number.

It is an amenable number.

28286705 is a deficient number, since it is larger than the sum of its proper divisors (5790967).

28286705 is a wasteful number, since it uses less digits than its factorization.

28286705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22275.

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 28286705 is about 5318.5247014562. The cubic root of 28286705 is about 304.6918144732.

The spelling of 28286705 in words is "twenty-eight million, two hundred eighty-six thousand, seven hundred five".