28708331 has 2 divisors, whose sum is σ = 28708332. Its totient is φ = 28708330.

The previous prime is 28708327. The next prime is 28708349. The reversal of 28708331 is 13380782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28708331 - 2² = 28708327 is a prime.

It is a super-2 number, since 2×28708331² = 1648336537611122, which contains 22 as substring.

It is a Chen prime.

It is equal to p_1782734 and since 28708331 and 1782734 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (28708931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14354165 + 14354166.

It is an arithmetic number, because the mean of its divisors is an integer number (14354166).

Almost surely, 2^28708331 is an apocalyptic number.

28708331 is a deficient number, since it is larger than the sum of its proper divisors (1).

28708331 is an equidigital number, since it uses as much as digits as its factorization.

28708331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 28708331 is about 5358.0155841505. The cubic root of 28708331 is about 306.1982105400.

The spelling of 28708331 in words is "twenty-eight million, seven hundred eight thousand, three hundred thirty-one".