211222221220121 has 4 divisors (see below), whose sum is σ = 211358230378932. Its totient is φ = 211086212061312.

The previous prime is 211222221220099. The next prime is 211222221220159. The reversal of 211222221220121 is 121022122222112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13016256918025 + 198205964302096 = 3607805^2 + 14078564^2 .

It is a cyclic number.

It is not a de Polignac number, because 211222221220121 - 2³⁸ = 210947343313177 is a prime.

It is a super-2 number, since 2×211222221220121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211222221120121) 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, 68004577076 + ... + 68004580181.

It is an arithmetic number, because the mean of its divisors is an integer number (52839557594733).

Almost surely, 2^{211222221220121} is an apocalyptic number.

It is an amenable number.

211222221220121 is a deficient number, since it is larger than the sum of its proper divisors (136009158811).

211222221220121 is a wasteful number, since it uses less digits than its factorization.

211222221220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136009158810.

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 211222221220121 its reverse (121022122222112), we get a palindrome (332244343442233).

The spelling of 211222221220121 in words is "two hundred eleven trillion, two hundred twenty-two billion, two hundred twenty-one million, two hundred twenty thousand, one hundred twenty-one".