202111211122121 has 6 divisors (see below), whose sum is σ = 235108959876810. Its totient is φ = 173238180961776.

The previous prime is 202111211122031. The next prime is 202111211122217. The reversal of 202111211122121 is 121221112111202.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 201694986148096 + 416224974025 = 14201936^2 + 645155^2 .

It is not a de Polignac number, because 202111211122121 - 2⁴⁶ = 131742466944457 is a prime.

It is a super-2 number, since 2×202111211122121² (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 = 202111211122093 and 202111211122102.

It is not an unprimeable number, because it can be changed into a prime (202111211122421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2062359297116 + ... + 2062359297213.

It is an arithmetic number, because the mean of its divisors is an integer number (39184826646135).

Almost surely, 2^{202111211122121} is an apocalyptic number.

It is an amenable number.

202111211122121 is a deficient number, since it is larger than the sum of its proper divisors (32997748754689).

202111211122121 is an equidigital number, since it uses as much as digits as its factorization.

202111211122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4124718594343 (or 4124718594336 counting only the distinct ones).

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

Adding to 202111211122121 its reverse (121221112111202), we get a palindrome (323332323233323).

The spelling of 202111211122121 in words is "two hundred two trillion, one hundred eleven billion, two hundred eleven million, one hundred twenty-two thousand, one hundred twenty-one".