28017857 has 12 divisors (see below), whose sum is σ = 33717780. Its totient is φ = 23186016.

The previous prime is 28017839. The next prime is 28017863. The reversal of 28017857 is 75871082.

It can be written as a sum of positive squares in 2 ways, for example, as 7187761 + 20830096 = 2681^2 + 4564^2 .

It is not a de Polignac number, because 28017857 - 2⁶ = 28017793 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28017857.

It is not an unprimeable number, because it can be changed into a prime (28011857) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 8438 + ... + 11279.

It is an arithmetic number, because the mean of its divisors is an integer number (2809815).

Almost surely, 2^28017857 is an apocalyptic number.

It is an amenable number.

28017857 is a deficient number, since it is larger than the sum of its proper divisors (5699923).

28017857 is a wasteful number, since it uses less digits than its factorization.

28017857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19760 (or 19753 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 28017857 is about 5293.1896810902. The cubic root of 28017857 is about 303.7234362901.

The spelling of 28017857 in words is "twenty-eight million, seventeen thousand, eight hundred fifty-seven".