28700287 has 16 divisors (see below), whose sum is σ = 36658944. Its totient is φ = 21816000.

The previous prime is 28700257. The next prime is 28700311. The reversal of 28700287 is 78200782.

It is a cyclic number.

It is not a de Polignac number, because 28700287 - 2¹⁵ = 28667519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28700257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1389 + ... + 7702.

It is an arithmetic number, because the mean of its divisors is an integer number (2291184).

Almost surely, 2^28700287 is an apocalyptic number.

28700287 is a deficient number, since it is larger than the sum of its proper divisors (7958657).

28700287 is a wasteful number, since it uses less digits than its factorization.

28700287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9150.

The product of its (nonzero) digits is 12544, while the sum is 34.

The square root of 28700287 is about 5357.2648805151. The cubic root of 28700287 is about 306.1696092199.

It can be divided in two parts, 28700 and 287, that multiplied together give a square (8236900 = 2870²).

The spelling of 28700287 in words is "twenty-eight million, seven hundred thousand, two hundred eighty-seven".