211231 has 2 divisors, whose sum is σ = 211232. Its totient is φ = 211230.

The previous prime is 211229. The next prime is 211241. The reversal of 211231 is 132112.

It is an a-pointer prime, because the next prime (211241) can be obtained adding 211231 to its sum of digits (10).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211231 - 2¹ = 211229 is a prime.

It is a super-2 number, since 2×211231² = 89237070722, which contains 22 as substring.

Together with 211229, it forms a pair of twin primes.

It is a plaindrome in base 11.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211241) 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, 105615 + 105616.

It is an arithmetic number, because the mean of its divisors is an integer number (105616).

2²¹¹²³¹ is an apocalyptic number.

211231 is a deficient number, since it is larger than the sum of its proper divisors (1).

211231 is an equidigital number, since it uses as much as digits as its factorization.

211231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12, while the sum is 10.

The square root of 211231 is about 459.5987380313. The cubic root of 211231 is about 59.5551356733. Note that the first 3 decimals are identical.

Adding to 211231 its reverse (132112), we get a palindrome (343343).

The spelling of 211231 in words is "two hundred eleven thousand, two hundred thirty-one".