2001211121111 has 4 divisors (see below), whose sum is σ = 2001349925400. Its totient is φ = 2001072316824.

The previous prime is 2001211121089. The next prime is 2001211121123. The reversal of 2001211121111 is 1111211121002.

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

It is a cyclic number.

It is not a de Polignac number, because 2001211121111 - 2⁶ = 2001211121047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001211151111) 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, 69380516 + ... + 69409353.

It is an arithmetic number, because the mean of its divisors is an integer number (500337481350).

Almost surely, 2^{2001211121111} is an apocalyptic number.

2001211121111 is a deficient number, since it is larger than the sum of its proper divisors (138804289).

2001211121111 is a wasteful number, since it uses less digits than its factorization.

2001211121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138804288.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 2001211121111 its reverse (1111211121002), we get a palindrome (3112422242113).

The spelling of 2001211121111 in words is "two trillion, one billion, two hundred eleven million, one hundred twenty-one thousand, one hundred eleven".