211211210221121 has 4 divisors (see below), whose sum is σ = 230412229332144. Its totient is φ = 192010191110100.

The previous prime is 211211210221111. The next prime is 211211210221147. The reversal of 211211210221121 is 121122012112112.

It is a happy number.

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 not a de Polignac number, because 211211210221121 - 2⁶ = 211211210221057 is a prime.

It is a super-2 number, since 2×211211210221121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211211210221093 and 211211210221102.

It is not an unprimeable number, because it can be changed into a prime (211211210221111) 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, 9600509555495 + ... + 9600509555516.

It is an arithmetic number, because the mean of its divisors is an integer number (57603057333036).

Almost surely, 2^{211211210221121} is an apocalyptic number.

It is an amenable number.

211211210221121 is a deficient number, since it is larger than the sum of its proper divisors (19201019111023).

211211210221121 is a wasteful number, since it uses less digits than its factorization.

211211210221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19201019111022.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 211211210221121 its reverse (121122012112112), we get a palindrome (332333222333233).

The spelling of 211211210221121 in words is "two hundred eleven trillion, two hundred eleven billion, two hundred ten million, two hundred twenty-one thousand, one hundred twenty-one".