2231 has 4 divisors (see below), whose sum is σ = 2352. Its totient is φ = 2112.

The previous prime is 2221. The next prime is 2237. The reversal of 2231 is 1322.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1322 = 2 ⋅661.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2231 is a prime.

It is a super-3 number, since 3×2231³ = 33313477173, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2237) 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 in 3 ways as a sum of consecutive naturals, for example, 26 + ... + 71.

It is an arithmetic number, because the mean of its divisors is an integer number (588).

2²²³¹ is an apocalyptic number.

2231 is a deficient number, since it is larger than the sum of its proper divisors (121).

2231 is an equidigital number, since it uses as much as digits as its factorization.

2231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120.

The product of its digits is 12, while the sum is 8.

The square root of 2231 is about 47.2334627145. The cubic root of 2231 is about 13.0667181496.

Adding to 2231 its reverse (1322), we get a palindrome (3553).

Subtracting from 2231 its reverse (1322), we obtain a palindrome (909).

The spelling of 2231 in words is "two thousand, two hundred thirty-one".