28912 has 20 divisors (see below), whose sum is σ = 60760. Its totient is φ = 13248.

The previous prime is 28909. The next prime is 28921. The reversal of 28912 is 21982.

It is a nialpdrome in base 14 and base 15.

It is a zygodrome in base 2 and base 15.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 139 + ... + 277.

It is an arithmetic number, because the mean of its divisors is an integer number (3038).

2²⁸⁹¹² is an apocalyptic number.

28912 is the 139-th pentagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30380).

28912 is an abundant number, since it is smaller than the sum of its proper divisors (31848).

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

28912 is a wasteful number, since it uses less digits than its factorization.

28912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160 (or 154 counting only the distinct ones).

The product of its digits is 288, while the sum is 22.

The square root of 28912 is about 170.0352904547. The cubic root of 28912 is about 30.6920604621.

The spelling of 28912 in words is "twenty-eight thousand, nine hundred twelve".