28866389 has 2 divisors, whose sum is σ = 28866390. Its totient is φ = 28866388.

The previous prime is 28866379. The next prime is 28866427. The reversal of 28866389 is 98366882.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20857489 + 8008900 = 4567^2 + 2830^2 .

It is a cyclic number.

It is not a de Polignac number, because 28866389 - 2¹² = 28862293 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28866329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14433194 + 14433195.

It is an arithmetic number, because the mean of its divisors is an integer number (14433195).

Almost surely, 2^28866389 is an apocalyptic number.

It is an amenable number.

28866389 is a deficient number, since it is larger than the sum of its proper divisors (1).

28866389 is an equidigital number, since it uses as much as digits as its factorization.

28866389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 995328, while the sum is 50.

The square root of 28866389 is about 5372.7450153530. The cubic root of 28866389 is about 306.7591223804.

The spelling of 28866389 in words is "twenty-eight million, eight hundred sixty-six thousand, three hundred eighty-nine".