28589440 has 128 divisors (see below), whose sum is σ = 77552640. Its totient is φ = 9984000.

The previous prime is 28589417. The next prime is 28589441. The reversal of 28589440 is 4498582.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 28589393 and 28589402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28589441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 218175 + ... + 218305.

It is an arithmetic number, because the mean of its divisors is an integer number (605880).

Almost surely, 2^28589440 is an apocalyptic number.

28589440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28589440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38776320).

28589440 is an abundant number, since it is smaller than the sum of its proper divisors (48963200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28589440 is a wasteful number, since it uses less digits than its factorization.

28589440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192 (or 180 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 40.

The square root of 28589440 is about 5346.9093876743. The cubic root of 28589440 is about 305.7749352489.

The spelling of 28589440 in words is "twenty-eight million, five hundred eighty-nine thousand, four hundred forty".