211231123 has 4 divisors (see below), whose sum is σ = 211441480. Its totient is φ = 211020768.

The previous prime is 211231109. The next prime is 211231147. The reversal of 211231123 is 321132112.

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 211231123 - 2⁵ = 211231091 is a prime.

It is a super-2 number, since 2×211231123² = 89237174647682258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211231097 and 211231106.

It is not an unprimeable number, because it can be changed into a prime (211231183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103665 + ... + 105682.

It is an arithmetic number, because the mean of its divisors is an integer number (52860370).

Almost surely, 2^211231123 is an apocalyptic number.

211231123 is a deficient number, since it is larger than the sum of its proper divisors (210357).

211231123 is a wasteful number, since it uses less digits than its factorization.

211231123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210356.

The product of its digits is 72, while the sum is 16.

The square root of 211231123 is about 14533.7924506992. The cubic root of 211231123 is about 595.5514723301.

Adding to 211231123 its reverse (321132112), we get a palindrome (532363235).

The spelling of 211231123 in words is "two hundred eleven million, two hundred thirty-one thousand, one hundred twenty-three".