2001211121 has 16 divisors (see below), whose sum is σ = 2471086464. Its totient is φ = 1578196224.

The previous prime is 2001211111. The next prime is 2001211127. The reversal of 2001211121 is 1211121002.

It is a cyclic number.

It is not a de Polignac number, because 2001211121 - 2¹⁴ = 2001194737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2001211127) 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, 7880 + ... + 63753.

It is an arithmetic number, because the mean of its divisors is an integer number (154442904).

Almost surely, 2^2001211121 is an apocalyptic number.

It is an amenable number.

2001211121 is a deficient number, since it is larger than the sum of its proper divisors (469875343).

2001211121 is a wasteful number, since it uses less digits than its factorization.

2001211121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71960.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 2001211121 is about 44734.8982451061. The cubic root of 2001211121 is about 1260.1753180505.

Adding to 2001211121 its reverse (1211121002), we get a palindrome (3212332123).

The spelling of 2001211121 in words is "two billion, one million, two hundred eleven thousand, one hundred twenty-one".