28812 has 30 divisors (see below), whose sum is σ = 78428. Its totient is φ = 8232.

The previous prime is 28807. The next prime is 28813. The reversal of 28812 is 21882.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 14.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28812.

It is not an unprimeable number, because it can be changed into a prime (28813) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 4113 + ... + 4119.

2²⁸⁸¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39214).

28812 is an abundant number, since it is smaller than the sum of its proper divisors (49616).

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

28812 is an equidigital number, since it uses as much as digits as its factorization.

28812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35 (or 12 counting only the distinct ones).

The product of its digits is 256, while the sum is 21.

The square root of 28812 is about 169.7409791417. The cubic root of 28812 is about 30.6566339792.

It can be divided in two parts, 288 and 12, that added together give a triangular number (300 = T₂₄).

The spelling of 28812 in words is "twenty-eight thousand, eight hundred twelve".