28105000 has 160 divisors (see below), whose sum is σ = 83223360. Its totient is φ = 8640000.

The previous prime is 28104997. The next prime is 28105001. The reversal of 28105000 is 50182.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (28105001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 384964 + ... + 385036.

It is an arithmetic number, because the mean of its divisors is an integer number (520146).

Almost surely, 2^28105000 is an apocalyptic number.

28105000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28105000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41611680).

28105000 is an abundant number, since it is smaller than the sum of its proper divisors (55118360).

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

28105000 is a wasteful number, since it uses less digits than its factorization.

28105000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 98 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 28105000 is about 5301.4149054757. The cubic root of 28105000 is about 304.0379973280.

Adding to 28105000 its reverse (50182), we get a palindrome (28155182).

The spelling of 28105000 in words is "twenty-eight million, one hundred five thousand".