211121211111221 has 16 divisors (see below), whose sum is σ = 217107059248128. Its totient is φ = 205175468361600.

The previous prime is 211121211111169. The next prime is 211121211111247. The reversal of 211121211111221 is 122111112121112.

211121211111221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 211121211111221 - 2¹⁴ = 211121211094837 is a prime.

It is a super-2 number, since 2×211121211111221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 211121211111193 and 211121211111202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211121211111721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61061411 + ... + 64426223.

It is an arithmetic number, because the mean of its divisors is an integer number (13569191203008).

Almost surely, 2^{211121211111221} is an apocalyptic number.

It is an amenable number.

211121211111221 is a deficient number, since it is larger than the sum of its proper divisors (5985848136907).

211121211111221 is a wasteful number, since it uses less digits than its factorization.

211121211111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3370772.

The product of its digits is 32, while the sum is 20.

Adding to 211121211111221 its reverse (122111112121112), we get a palindrome (333232323232333).

The spelling of 211121211111221 in words is "two hundred eleven trillion, one hundred twenty-one billion, two hundred eleven million, one hundred eleven thousand, two hundred twenty-one".