28681566 has 8 divisors (see below), whose sum is σ = 57363144. Its totient is φ = 9560520.

The previous prime is 28681531. The next prime is 28681577. The reversal of 28681566 is 66518682.

It is a sphenic number, since it is the product of 3 distinct primes.

28681566 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2390125 + ... + 2390136.

It is an arithmetic number, because the mean of its divisors is an integer number (7170393).

Almost surely, 2^28681566 is an apocalyptic number.

28681566 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28681566 is a wasteful number, since it uses less digits than its factorization.

28681566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4780266.

The product of its digits is 138240, while the sum is 42.

The square root of 28681566 is about 5355.5173419568. The cubic root of 28681566 is about 306.1030239627.

The spelling of 28681566 in words is "twenty-eight million, six hundred eighty-one thousand, five hundred sixty-six".