28256705 has 8 divisors (see below), whose sum is σ = 35692800. Its totient is φ = 21415536.

The previous prime is 28256687. The next prime is 28256713. The reversal of 28256705 is 50765282.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28256705 is a prime.

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 7 ways as a sum of consecutive naturals, for example, 148625 + ... + 148814.

It is an arithmetic number, because the mean of its divisors is an integer number (4461600).

Almost surely, 2^28256705 is an apocalyptic number.

It is an amenable number.

28256705 is a deficient number, since it is larger than the sum of its proper divisors (7436095).

28256705 is a wasteful number, since it uses less digits than its factorization.

28256705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297463.

The product of its (nonzero) digits is 33600, while the sum is 35.

The square root of 28256705 is about 5315.7036222875. The cubic root of 28256705 is about 304.5840608152.

The spelling of 28256705 in words is "twenty-eight million, two hundred fifty-six thousand, seven hundred five".