212111221111 has 4 divisors (see below), whose sum is σ = 212998716000. Its totient is φ = 211223726224.

The previous prime is 212111221099. The next prime is 212111221117. The reversal of 212111221111 is 111122111212.

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 212111221111 - 2⁵ = 212111221079 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212111221117) 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, 443747086 + ... + 443747563.

It is an arithmetic number, because the mean of its divisors is an integer number (53249679000).

Almost surely, 2^212111221111 is an apocalyptic number.

212111221111 is a deficient number, since it is larger than the sum of its proper divisors (887494889).

212111221111 is an equidigital number, since it uses as much as digits as its factorization.

212111221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887494888.

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

Adding to 212111221111 its reverse (111122111212), we get a palindrome (323233332323).

The spelling of 212111221111 in words is "two hundred twelve billion, one hundred eleven million, two hundred twenty-one thousand, one hundred eleven".