2001220111111 has 24 divisors (see below), whose sum is σ = 2294240299920. Its totient is φ = 1739938427136.

The previous prime is 2001220111061. The next prime is 2001220111117. The reversal of 2001220111111 is 1111110221002.

It is a happy number.

It is not a de Polignac number, because 2001220111111 - 2¹⁵ = 2001220078343 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001220111091 and 2001220111100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001220111117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1245766 + ... + 2356771.

It is an arithmetic number, because the mean of its divisors is an integer number (95593345830).

Almost surely, 2^{2001220111111} is an apocalyptic number.

2001220111111 is a deficient number, since it is larger than the sum of its proper divisors (293020188809).

2001220111111 is a wasteful number, since it uses less digits than its factorization.

2001220111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3602755 (or 3602742 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 2001220111111 its reverse (1111110221002), we get a palindrome (3112330332113).

The spelling of 2001220111111 in words is "two trillion, one billion, two hundred twenty million, one hundred eleven thousand, one hundred eleven".