28927840 has 24 divisors (see below), whose sum is σ = 68342400. Its totient is φ = 11571072.

The previous prime is 28927817. The next prime is 28927879. The reversal of 28927840 is 4872982.

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 = 28927793 and 28927802.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 90240 + ... + 90559.

It is an arithmetic number, because the mean of its divisors is an integer number (2847600).

Almost surely, 2^28927840 is an apocalyptic number.

28927840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28927840 is an abundant number, since it is smaller than the sum of its proper divisors (39414560).

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

28927840 is a wasteful number, since it uses less digits than its factorization.

28927840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180814 (or 180806 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 28927840 is about 5378.4607463474. The cubic root of 28927840 is about 306.9766451904.

The spelling of 28927840 in words is "twenty-eight million, nine hundred twenty-seven thousand, eight hundred forty".