28904671 has 12 divisors (see below), whose sum is σ = 30185568. Its totient is φ = 27664032.

The previous prime is 28904647. The next prime is 28904717. The reversal of 28904671 is 17640982.

It is not a de Polignac number, because 28904671 - 2⁵ = 28904639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28904671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28904621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 210915 + ... + 211051.

It is an arithmetic number, because the mean of its divisors is an integer number (2515464).

Almost surely, 2^28904671 is an apocalyptic number.

28904671 is a deficient number, since it is larger than the sum of its proper divisors (1280897).

28904671 is an equidigital number, since it uses as much as digits as its factorization.

28904671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 28904671 is about 5376.3064458790. The cubic root of 28904671 is about 306.8946683179.

The spelling of 28904671 in words is "twenty-eight million, nine hundred four thousand, six hundred seventy-one".