28660889 has 2 divisors, whose sum is σ = 28660890. Its totient is φ = 28660888.

The previous prime is 28660867. The next prime is 28660909. The reversal of 28660889 is 98806682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24334489 + 4326400 = 4933^2 + 2080^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28660889 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28663889) 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, 14330444 + 14330445.

It is an arithmetic number, because the mean of its divisors is an integer number (14330445).

Almost surely, 2^28660889 is an apocalyptic number.

It is an amenable number.

28660889 is a deficient number, since it is larger than the sum of its proper divisors (1).

28660889 is an equidigital number, since it uses as much as digits as its factorization.

28660889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 331776, while the sum is 47.

The square root of 28660889 is about 5353.5865548247. The cubic root of 28660889 is about 306.0294480894.

The spelling of 28660889 in words is "twenty-eight million, six hundred sixty thousand, eight hundred eighty-nine".