28133500 has 24 divisors (see below), whose sum is σ = 61444656. Its totient is φ = 11253200.

The previous prime is 28133491. The next prime is 28133507. The reversal of 28133500 is 533182.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28133507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27634 + ... + 28633.

It is an arithmetic number, because the mean of its divisors is an integer number (2560194).

Almost surely, 2^28133500 is an apocalyptic number.

28133500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28133500 is an abundant number, since it is smaller than the sum of its proper divisors (33311156).

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

28133500 is a wasteful number, since it uses less digits than its factorization.

28133500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56286 (or 56274 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 28133500 is about 5304.1021860443. The cubic root of 28133500 is about 304.1407329696.

Adding to 28133500 its reverse (533182), we get a palindrome (28666682).

The spelling of 28133500 in words is "twenty-eight million, one hundred thirty-three thousand, five hundred".