211121111210221 has 4 divisors (see below), whose sum is σ = 212416332751552. Its totient is φ = 209825889668892.

The previous prime is 211121111210213. The next prime is 211121111210327. The reversal of 211121111210221 is 122012111121112.

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 211121111210221 - 2³ = 211121111210213 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 (211121111210201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 647610770421 + ... + 647610770746.

It is an arithmetic number, because the mean of its divisors is an integer number (53104083187888).

Almost surely, 2^{211121111210221} is an apocalyptic number.

It is an amenable number.

211121111210221 is a deficient number, since it is larger than the sum of its proper divisors (1295221541331).

211121111210221 is a wasteful number, since it uses less digits than its factorization.

211121111210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1295221541330.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 211121111210221 its reverse (122012111121112), we get a palindrome (333133222331333).

The spelling of 211121111210221 in words is "two hundred eleven trillion, one hundred twenty-one billion, one hundred eleven million, two hundred ten thousand, two hundred twenty-one".