281940 has 48 divisors (see below), whose sum is σ = 817152. Its totient is φ = 72576.

The previous prime is 281933. The next prime is 281947. The reversal of 281940 is 49182.

It is an interprime number because it is at equal distance from previous prime (281933) and next prime (281947).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 281940.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2157 + ... + 2283.

It is an arithmetic number, because the mean of its divisors is an integer number (17024).

2²⁸¹⁹⁴⁰ is an apocalyptic number.

281940 is a gapful number since it is divisible by the number (20) 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 281940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (408576).

281940 is an abundant number, since it is smaller than the sum of its proper divisors (535212).

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

281940 is a wasteful number, since it uses less digits than its factorization.

281940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 281940 is about 530.9802256205. The cubic root of 281940 is about 65.5720707005.

It can be divided in two parts, 281 and 940, that added together give a palindrome (1221).

The spelling of 281940 in words is "two hundred eighty-one thousand, nine hundred forty".