281800 has 24 divisors (see below), whose sum is σ = 655650. Its totient is φ = 112640.

The previous prime is 281797. The next prime is 281803. The reversal of 281800 is 8182.

It is a happy number.

281800 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (281797) and next prime (281803).

It can be written as a sum of positive squares in 3 ways, for example, as 116964 + 164836 = 342^2 + 406^2 .

It is a super-2 number, since 2×281800² = 158822480000, which contains 22 as substring.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 505 + ... + 904.

2²⁸¹⁸⁰⁰ is an apocalyptic number.

281800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

281800 is an abundant number, since it is smaller than the sum of its proper divisors (373850).

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

281800 is a wasteful number, since it uses less digits than its factorization.

281800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1425 (or 1416 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 281800 is about 530.8483775995. The cubic root of 281800 is about 65.5612154242.

Adding to 281800 its reverse (8182), we get a palindrome (289982).

It can be divided in two parts, 281 and 800, that added together give a triangular number (1081 = T₄₆).

The spelling of 281800 in words is "two hundred eighty-one thousand, eight hundred".