28290320 has 20 divisors (see below), whose sum is σ = 65775180. Its totient is φ = 11316096.

The previous prime is 28290319. The next prime is 28290331. The reversal of 28290320 is 2309282.

It can be written as a sum of positive squares in 2 ways, for example, as 7203856 + 21086464 = 2684^2 + 4592^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 28290320.

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, 176735 + ... + 176894.

It is an arithmetic number, because the mean of its divisors is an integer number (3288759).

Almost surely, 2^28290320 is an apocalyptic number.

28290320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28290320 is an abundant number, since it is smaller than the sum of its proper divisors (37484860).

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

28290320 is a wasteful number, since it uses less digits than its factorization.

28290320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353642 (or 353636 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 28290320 is about 5318.8645404823. The cubic root of 28290320 is about 304.7047936448.

The spelling of 28290320 in words is "twenty-eight million, two hundred ninety thousand, three hundred twenty".