28185289 has 8 divisors (see below), whose sum is σ = 31402368. Its totient is φ = 25077360.

The previous prime is 28185271. The next prime is 28185299. The reversal of 28185289 is 98258182.

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

It is not a de Polignac number, because 28185289 - 2⁵ = 28185257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28185239) 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, 26742 + ... + 27775.

It is an arithmetic number, because the mean of its divisors is an integer number (3925296).

Almost surely, 2^28185289 is an apocalyptic number.

It is an amenable number.

28185289 is a deficient number, since it is larger than the sum of its proper divisors (3217079).

28185289 is a wasteful number, since it uses less digits than its factorization.

28185289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54575.

The product of its digits is 92160, while the sum is 43.

The square root of 28185289 is about 5308.9819174678. The cubic root of 28185289 is about 304.3272424006.

The spelling of 28185289 in words is "twenty-eight million, one hundred eighty-five thousand, two hundred eighty-nine".