28556831 has 2 divisors, whose sum is σ = 28556832. Its totient is φ = 28556830.

The previous prime is 28556809. The next prime is 28556873. The reversal of 28556831 is 13865582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28556831 - 2¹⁸ = 28294687 is a prime.

It is a super-2 number, since 2×28556831² = 1630985193525122, which contains 22 as substring.

It is a Sophie Germain prime.

It is equal to p_1773929 and since 28556831 and 1773929 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28556881) by changing a digit.

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 as a sum of consecutive naturals, namely, 14278415 + 14278416.

It is an arithmetic number, because the mean of its divisors is an integer number (14278416).

Almost surely, 2^28556831 is an apocalyptic number.

28556831 is a deficient number, since it is larger than the sum of its proper divisors (1).

28556831 is an equidigital number, since it uses as much as digits as its factorization.

28556831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 38.

The square root of 28556831 is about 5343.8591860190. The cubic root of 28556831 is about 305.6586358013.

The spelling of 28556831 in words is "twenty-eight million, five hundred fifty-six thousand, eight hundred thirty-one".