28168331 has 2 divisors, whose sum is σ = 28168332. Its totient is φ = 28168330.

The previous prime is 28168313. The next prime is 28168333. The reversal of 28168331 is 13386182.

It is a happy number.

Together with previous prime (28168313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28168331 - 2⁶ = 28168267 is a prime.

It is a super-2 number, since 2×28168331² = 1586909742651122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 28168333, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28168333) by changing a digit.

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 as a sum of consecutive naturals, namely, 14084165 + 14084166.

It is an arithmetic number, because the mean of its divisors is an integer number (14084166).

Almost surely, 2^28168331 is an apocalyptic number.

28168331 is a deficient number, since it is larger than the sum of its proper divisors (1).

28168331 is an equidigital number, since it uses as much as digits as its factorization.

28168331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 32.

The square root of 28168331 is about 5307.3845724613. The cubic root of 28168331 is about 304.2661961726.

The spelling of 28168331 in words is "twenty-eight million, one hundred sixty-eight thousand, three hundred thirty-one".