28489440 has 192 divisors, whose sum is σ = 104993280. Its totient is φ = 6359040.

The previous prime is 28489429. The next prime is 28489441. The reversal of 28489440 is 4498482.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28489441) 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 31 ways as a sum of consecutive naturals, for example, 204891 + ... + 205029.

It is an arithmetic number, because the mean of its divisors is an integer number (546840).

Almost surely, 2^28489440 is an apocalyptic number.

28489440 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 28489440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52496640).

28489440 is an abundant number, since it is smaller than the sum of its proper divisors (76503840).

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

28489440 is a wasteful number, since it uses less digits than its factorization.

28489440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225 (or 217 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 39.

The square root of 28489440 is about 5337.5499997658. The cubic root of 28489440 is about 305.4180060910.

The spelling of 28489440 in words is "twenty-eight million, four hundred eighty-nine thousand, four hundred forty".