28658689 has 2 divisors, whose sum is σ = 28658690. Its totient is φ = 28658688.

The previous prime is 28658687. The next prime is 28658717. The reversal of 28658689 is 98685682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 8363664 = 4505^2 + 2892^2 .

It is a cyclic number.

It is not a de Polignac number, because 28658689 - 2¹ = 28658687 is a prime.

Together with 28658687, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28658681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14329344 + 14329345.

It is an arithmetic number, because the mean of its divisors is an integer number (14329345).

Almost surely, 2^28658689 is an apocalyptic number.

It is an amenable number.

28658689 is a deficient number, since it is larger than the sum of its proper divisors (1).

28658689 is an equidigital number, since it uses as much as digits as its factorization.

28658689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1658880, while the sum is 52.

The square root of 28658689 is about 5353.3810811486. The cubic root of 28658689 is about 306.0216176506.

The spelling of 28658689 in words is "twenty-eight million, six hundred fifty-eight thousand, six hundred eighty-nine".