28646289 has 24 divisors (see below), whose sum is σ = 47648640. Its totient is φ = 16244928.

The previous prime is 28646239. The next prime is 28646333. The reversal of 28646289 is 98264682.

It is not a de Polignac number, because 28646289 - 2⁹ = 28645777 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28646209) 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 in 23 ways as a sum of consecutive naturals, for example, 6972 + ... + 10290.

It is an arithmetic number, because the mean of its divisors is an integer number (1985360).

Almost surely, 2^28646289 is an apocalyptic number.

It is an amenable number.

28646289 is a deficient number, since it is larger than the sum of its proper divisors (19002351).

28646289 is a wasteful number, since it uses less digits than its factorization.

28646289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3469 (or 3466 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The square root of 28646289 is about 5352.2228092635. Note that the first 3 decimals coincide. The cubic root of 28646289 is about 305.9774749535.

The spelling of 28646289 in words is "twenty-eight million, six hundred forty-six thousand, two hundred eighty-nine".