28581489 has 24 divisors (see below), whose sum is σ = 42556800. Its totient is φ = 18476640.

The previous prime is 28581481. The next prime is 28581493. The reversal of 28581489 is 98418582.

It is a happy number.

28581489 is a `hidden beast` number, since 28 + 581 + 48 + 9 = 666.

It is not a de Polignac number, because 28581489 - 2³ = 28581481 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28581481) 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, 43042 + ... + 43700.

It is an arithmetic number, because the mean of its divisors is an integer number (1773200).

Almost surely, 2^28581489 is an apocalyptic number.

It is an amenable number.

28581489 is a deficient number, since it is larger than the sum of its proper divisors (13975311).

28581489 is a wasteful number, since it uses less digits than its factorization.

28581489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 805 (or 802 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 28581489 is about 5346.1658223441. The cubic root of 28581489 is about 305.7465862976.

The spelling of 28581489 in words is "twenty-eight million, five hundred eighty-one thousand, four hundred eighty-nine".