28684909 has 8 divisors (see below), whose sum is σ = 31603680. Its totient is φ = 25818000.

The previous prime is 28684897. The next prime is 28684921. The reversal of 28684909 is 90948682.

It is an interprime number because it is at equal distance from previous prime (28684897) and next prime (28684921).

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 28684909 - 2¹³ = 28676717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28684949) 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, 11799 + ... + 14020.

It is an arithmetic number, because the mean of its divisors is an integer number (3950460).

Almost surely, 2^28684909 is an apocalyptic number.

It is an amenable number.

28684909 is a deficient number, since it is larger than the sum of its proper divisors (2918771).

28684909 is a wasteful number, since it uses less digits than its factorization.

28684909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25931.

The product of its (nonzero) digits is 248832, while the sum is 46.

The square root of 28684909 is about 5355.8294408990. The cubic root of 28684909 is about 306.1149161847.

It can be divided in two parts, 2868 and 4909, that added together give a palindrome (7777).

The spelling of 28684909 in words is "twenty-eight million, six hundred eighty-four thousand, nine hundred nine".