281988 has 48 divisors (see below), whose sum is σ = 837760. Its totient is φ = 80352.

The previous prime is 281971. The next prime is 281989. The reversal of 281988 is 889182.

281988 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 281988.

It is not an unprimeable number, because it can be changed into a prime (281989) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 570 + ... + 942.

2²⁸¹⁹⁸⁸ is an apocalyptic number.

281988 is a gapful number since it is divisible by the number (28) 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 281988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (418880).

281988 is an abundant number, since it is smaller than the sum of its proper divisors (555772).

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

281988 is a wasteful number, since it uses less digits than its factorization.

281988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393 (or 385 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 281988 is about 531.0254231202. The cubic root of 281988 is about 65.5757916822.

It can be divided in two parts, 28 and 1988, that added together give a triangular number (2016 = T₆₃).

The spelling of 281988 in words is "two hundred eighty-one thousand, nine hundred eighty-eight".