212111123 has 4 divisors (see below), whose sum is σ = 242412720. Its totient is φ = 181809528.

The previous prime is 212111111. The next prime is 212111147. The reversal of 212111123 is 321111212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212111123 is a prime.

It is a super-2 number, since 2×212111123² = 89982257000642258, 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 = 212111098 and 212111107.

It is not an unprimeable number, because it can be changed into a prime (212111153) 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, 15150788 + ... + 15150801.

It is an arithmetic number, because the mean of its divisors is an integer number (60603180).

Almost surely, 2^212111123 is an apocalyptic number.

212111123 is a deficient number, since it is larger than the sum of its proper divisors (30301597).

212111123 is an equidigital number, since it uses as much as digits as its factorization.

212111123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30301596.

The product of its digits is 24, while the sum is 14.

The square root of 212111123 is about 14564.0352581282. The cubic root of 212111123 is about 596.3773594421.

Adding to 212111123 its reverse (321111212), we get a palindrome (533222335).

The spelling of 212111123 in words is "two hundred twelve million, one hundred eleven thousand, one hundred twenty-three".