201211211121 has 16 divisors (see below), whose sum is σ = 279958339584. Its totient is φ = 128302957904.

The previous prime is 201211211111. The next prime is 201211211129. The reversal of 201211211121 is 121112112102.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 201211211121 - 2²² = 201207016817 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 201211211121.

It is not an unprimeable number, because it can be changed into a prime (201211211129) 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 15 ways as a sum of consecutive naturals, for example, 1990810 + ... + 2089436.

It is an arithmetic number, because the mean of its divisors is an integer number (17497396224).

Almost surely, 2^201211211121 is an apocalyptic number.

It is an amenable number.

201211211121 is a deficient number, since it is larger than the sum of its proper divisors (78747128463).

201211211121 is a wasteful number, since it uses less digits than its factorization.

201211211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128220.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 201211211121 its reverse (121112112102), we get a palindrome (322323323223).

The spelling of 201211211121 in words is "two hundred one billion, two hundred eleven million, two hundred eleven thousand, one hundred twenty-one".