28258287 has 4 divisors (see below), whose sum is σ = 37677720. Its totient is φ = 18838856.

The previous prime is 28258277. The next prime is 28258289. The reversal of 28258287 is 78285282.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28258287 - 2⁷ = 28258159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28258289) 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 3 ways as a sum of consecutive naturals, for example, 4709712 + ... + 4709717.

It is an arithmetic number, because the mean of its divisors is an integer number (9419430).

Almost surely, 2^28258287 is an apocalyptic number.

28258287 is a deficient number, since it is larger than the sum of its proper divisors (9419433).

28258287 is an equidigital number, since it uses as much as digits as its factorization.

28258287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9419432.

The product of its digits is 143360, while the sum is 42.

The square root of 28258287 is about 5315.8524245882. The cubic root of 28258287 is about 304.5897449292.

The spelling of 28258287 in words is "twenty-eight million, two hundred fifty-eight thousand, two hundred eighty-seven".