201021122121 has 16 divisors (see below), whose sum is σ = 282147840000. Its totient is φ = 126954889488.

The previous prime is 201021122053. The next prime is 201021122129. The reversal of 201021122121 is 121221120102.

It is not a de Polignac number, because 201021122121 - 2¹³ = 201021113929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201021122121.

It is not an unprimeable number, because it can be changed into a prime (201021122129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1414120 + ... + 1549766.

It is an arithmetic number, because the mean of its divisors is an integer number (17634240000).

Almost surely, 2^201021122121 is an apocalyptic number.

It is an amenable number.

201021122121 is a deficient number, since it is larger than the sum of its proper divisors (81126717879).

201021122121 is a wasteful number, since it uses less digits than its factorization.

201021122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161668.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 201021122121 its reverse (121221120102), we get a palindrome (322242242223).

The spelling of 201021122121 in words is "two hundred one billion, twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".