42281 has 2 divisors, whose sum is σ = 42282. Its totient is φ = 42280.

The previous prime is 42257. The next prime is 42283. The reversal of 42281 is 18224.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42025 + 256 = 205^2 + 16^2 .

It is a cyclic number.

It is not a de Polignac number, because 42281 - 2¹⁰ = 41257 is a prime.

It is a super-2 number, since 2×42281² = 3575365922, which contains 22 as substring.

Together with 42283, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42283) 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 as a sum of consecutive naturals, namely, 21140 + 21141.

It is an arithmetic number, because the mean of its divisors is an integer number (21141).

2⁴²²⁸¹ is an apocalyptic number.

It is an amenable number.

42281 is a deficient number, since it is larger than the sum of its proper divisors (1).

42281 is an equidigital number, since it uses as much as digits as its factorization.

42281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 128, while the sum is 17.

The square root of 42281 is about 205.6234422433. The cubic root of 42281 is about 34.8376151164.

It can be divided in two parts, 42 and 281, that added together give a palindrome (323).

The spelling of 42281 in words is "forty-two thousand, two hundred eighty-one".