2111211221 has 4 divisors (see below), whose sum is σ = 2412812832. Its totient is φ = 1809609612.

The previous prime is 2111211203. The next prime is 2111211229. The reversal of 2111211221 is 1221121112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2111211221 - 2²² = 2107016917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2111211196 and 2111211205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2111211229) 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, 150800795 + ... + 150800808.

It is an arithmetic number, because the mean of its divisors is an integer number (603203208).

Almost surely, 2^2111211221 is an apocalyptic number.

It is an amenable number.

2111211221 is a deficient number, since it is larger than the sum of its proper divisors (301601611).

2111211221 is an equidigital number, since it uses as much as digits as its factorization.

2111211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301601610.

The product of its digits is 16, while the sum is 14.

The square root of 2111211221 is about 45947.9185709211. The cubic root of 2111211221 is about 1282.8539876325.

Adding to 2111211221 its reverse (1221121112), we get a palindrome (3332332333).

The spelling of 2111211221 in words is "two billion, one hundred eleven million, two hundred eleven thousand, two hundred twenty-one".