281808 has 60 divisors (see below), whose sum is σ = 838240. Its totient is φ = 88128.

The previous prime is 281807. The next prime is 281833. The reversal of 281808 is 808182.

281808 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 281808.

It is not an unprimeable number, because it can be changed into a prime (281803) 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 11 ways as a sum of consecutive naturals, for example, 2685 + ... + 2787.

2²⁸¹⁸⁰⁸ 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 281808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (419120).

281808 is an abundant number, since it is smaller than the sum of its proper divisors (556432).

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

281808 is a wasteful number, since it uses less digits than its factorization.

281808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 281808 is about 530.8559126543. The cubic root of 281808 is about 65.5618358225.

It can be divided in two parts, 281 and 808, that added together give a square (1089 = 33²).

The spelling of 281808 in words is "two hundred eighty-one thousand, eight hundred eight".