28443440 has 40 divisors (see below), whose sum is σ = 66558240. Its totient is φ = 11303936.

The previous prime is 28443439. The next prime is 28443469. The reversal of 28443440 is 4434482.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12296 + ... + 14424.

It is an arithmetic number, because the mean of its divisors is an integer number (1663956).

Almost surely, 2^28443440 is an apocalyptic number.

28443440 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 28443440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33279120).

28443440 is an abundant number, since it is smaller than the sum of its proper divisors (38114800).

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

28443440 is a wasteful number, since it uses less digits than its factorization.

28443440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2309 (or 2303 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 29.

The square root of 28443440 is about 5333.2391658353. The cubic root of 28443440 is about 305.2535381744.

The spelling of 28443440 in words is "twenty-eight million, four hundred forty-three thousand, four hundred forty".