281531 has 2 divisors, whose sum is σ = 281532. Its totient is φ = 281530.

The previous prime is 281527. The next prime is 281539. The reversal of 281531 is 135182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 281531 - 2² = 281527 is a prime.

It is a super-2 number, since 2×281531² = 158519407922, which contains 22 as substring.

It is a plaindrome in base 16.

It is a zygodrome in base 16.

It is not a weakly prime, because it can be changed into another prime (281539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140765 + 140766.

It is an arithmetic number, because the mean of its divisors is an integer number (140766).

2²⁸¹⁵³¹ is an apocalyptic number.

281531 is a deficient number, since it is larger than the sum of its proper divisors (1).

281531 is an equidigital number, since it uses as much as digits as its factorization.

281531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 240, while the sum is 20.

The square root of 281531 is about 530.5949490902. The cubic root of 281531 is about 65.5403476911.

The spelling of 281531 in words is "two hundred eighty-one thousand, five hundred thirty-one".