231281 has 4 divisors (see below), whose sum is σ = 236964. Its totient is φ = 225600.

The previous prime is 231277. The next prime is 231289. The reversal of 231281 is 182132.

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

It can be written as a sum of positive squares in 2 ways, for example, as 128881 + 102400 = 359^2 + 320^2 .

It is a cyclic number.

It is not a de Polignac number, because 231281 - 2² = 231277 is a prime.

It is a super-2 number, since 2×231281² = 106981801922, which contains 22 as substring.

It is a Duffinian number.

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 231281.

It is not an unprimeable number, because it can be changed into a prime (231289) 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, 2780 + ... + 2861.

It is an arithmetic number, because the mean of its divisors is an integer number (59241).

2²³¹²⁸¹ is an apocalyptic number.

It is an amenable number.

231281 is a deficient number, since it is larger than the sum of its proper divisors (5683).

231281 is an equidigital number, since it uses as much as digits as its factorization.

231281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5682.

The product of its digits is 96, while the sum is 17.

The square root of 231281 is about 480.9168327268. The cubic root of 231281 is about 61.3827939353.

It can be divided in two parts, 231 and 281, that added together give a 9-th power (512 = 2⁹).

The spelling of 231281 in words is "two hundred thirty-one thousand, two hundred eighty-one".