212123211 has 4 divisors (see below), whose sum is σ = 282830952. Its totient is φ = 141415472.

The previous prime is 212123203. The next prime is 212123237. The reversal of 212123211 is 112321212.

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 212123211 - 2³ = 212123203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (212123251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35353866 + ... + 35353871.

It is an arithmetic number, because the mean of its divisors is an integer number (70707738).

Almost surely, 2^212123211 is an apocalyptic number.

212123211 is a deficient number, since it is larger than the sum of its proper divisors (70707741).

212123211 is an equidigital number, since it uses as much as digits as its factorization.

212123211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70707740.

The product of its digits is 48, while the sum is 15.

The square root of 212123211 is about 14564.4502470914. The cubic root of 212123211 is about 596.3886882093.

Adding to 212123211 its reverse (112321212), we get a palindrome (324444423).

The spelling of 212123211 in words is "two hundred twelve million, one hundred twenty-three thousand, two hundred eleven".