281491 has 4 divisors (see below), whose sum is σ = 321712. Its totient is φ = 241272.

The previous prime is 281431. The next prime is 281509. The reversal of 281491 is 194182.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 281491 - 2⁷ = 281363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (281431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20100 + ... + 20113.

It is an arithmetic number, because the mean of its divisors is an integer number (80428).

2²⁸¹⁴⁹¹ is an apocalyptic number.

281491 is a deficient number, since it is larger than the sum of its proper divisors (40221).

281491 is an equidigital number, since it uses as much as digits as its factorization.

281491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40220.

The product of its digits is 576, while the sum is 25.

The square root of 281491 is about 530.5572542148. The cubic root of 281491 is about 65.5372435473.

The spelling of 281491 in words is "two hundred eighty-one thousand, four hundred ninety-one".