211211212201221 has 32 divisors (see below), whose sum is σ = 302553951687936. Its totient is φ = 130583085696000.

The previous prime is 211211212201183. The next prime is 211211212201247. The reversal of 211211212201221 is 122102212112112.

It is not a de Polignac number, because 211211212201221 - 2²⁶ = 211211145092357 is a prime.

It is a super-2 number, since 2×211211212201221² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211211212201261) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10447570 + ... + 23055891.

It is an arithmetic number, because the mean of its divisors is an integer number (9454810990248).

Almost surely, 2^{211211212201221} is an apocalyptic number.

It is an amenable number.

211211212201221 is a deficient number, since it is larger than the sum of its proper divisors (91342739486715).

211211212201221 is a wasteful number, since it uses less digits than its factorization.

211211212201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33505293.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 211211212201221 its reverse (122102212112112), we get a palindrome (333313424313333).

The spelling of 211211212201221 in words is "two hundred eleven trillion, two hundred eleven billion, two hundred twelve million, two hundred one thousand, two hundred twenty-one".