2123111231 has 4 divisors (see below), whose sum is σ = 2126644464. Its totient is φ = 2119578000.

The previous prime is 2123111219. The next prime is 2123111261. The reversal of 2123111231 is 1321113212.

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

It is a cyclic number.

It is not a de Polignac number, because 2123111231 - 2³⁰ = 1049369407 is a prime.

It is a super-2 number, since 2×2123111231² = 9015202598396670722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2123111261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1765715 + ... + 1766916.

It is an arithmetic number, because the mean of its divisors is an integer number (531661116).

Almost surely, 2^2123111231 is an apocalyptic number.

2123111231 is a deficient number, since it is larger than the sum of its proper divisors (3533233).

2123111231 is an equidigital number, since it uses as much as digits as its factorization.

2123111231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3533232.

The product of its digits is 72, while the sum is 17.

The square root of 2123111231 is about 46077.2311559625. The cubic root of 2123111231 is about 1285.2597759912.

Adding to 2123111231 its reverse (1321113212), we get a palindrome (3444224443).

The spelling of 2123111231 in words is "two billion, one hundred twenty-three million, one hundred eleven thousand, two hundred thirty-one".