28919040 has 144 divisors (see below), whose sum is σ = 98013888. Its totient is φ = 7241728.

The previous prime is 28919039. The next prime is 28919047. The reversal of 28919040 is 4091982.

It is a junction number, because it is equal to n+sod(n) for n = 28918992 and 28919010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28919047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65059 + ... + 65501.

It is an arithmetic number, because the mean of its divisors is an integer number (680652).

Almost surely, 2^28919040 is an apocalyptic number.

28919040 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 28919040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49006944).

28919040 is an abundant number, since it is smaller than the sum of its proper divisors (69094848).

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

28919040 is a wasteful number, since it uses less digits than its factorization.

28919040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484 (or 470 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 28919040 is about 5377.6426061984. The cubic root of 28919040 is about 306.9455140673.

The spelling of 28919040 in words is "twenty-eight million, nine hundred nineteen thousand, forty".