28081009 has 8 divisors (see below), whose sum is σ = 31622400. Its totient is φ = 24704400.

The previous prime is 28081007. The next prime is 28081033. The reversal of 28081009 is 90018082.

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

It is a cyclic number.

It is not a de Polignac number, because 28081009 - 2¹ = 28081007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28081007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40834 + ... + 41515.

It is an arithmetic number, because the mean of its divisors is an integer number (3952800).

Almost surely, 2^28081009 is an apocalyptic number.

It is an amenable number.

28081009 is a deficient number, since it is larger than the sum of its proper divisors (3541391).

28081009 is a wasteful number, since it uses less digits than its factorization.

28081009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82391.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 28081009 is about 5299.1517245688. The cubic root of 28081009 is about 303.9514616930.

The spelling of 28081009 in words is "twenty-eight million, eighty-one thousand, nine".