212281 has 2 divisors, whose sum is σ = 212282. Its totient is φ = 212280.

The previous prime is 212243. The next prime is 212293. The reversal of 212281 is 182212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 210681 + 1600 = 459^2 + 40^2 .

It is a cyclic number.

It is not a de Polignac number, because 212281 - 2¹¹ = 210233 is a prime.

It is a super-2 number, since 2×212281² = 90126445922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (212081) 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, 106140 + 106141.

It is an arithmetic number, because the mean of its divisors is an integer number (106141).

2²¹²²⁸¹ is an apocalyptic number.

It is an amenable number.

212281 is a deficient number, since it is larger than the sum of its proper divisors (1).

212281 is an equidigital number, since it uses as much as digits as its factorization.

212281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64, while the sum is 16.

The square root of 212281 is about 460.7396227806. The cubic root of 212281 is about 59.6536527211.

Adding to 212281 its reverse (182212), we get a palindrome (394493).

The spelling of 212281 in words is "two hundred twelve thousand, two hundred eighty-one".