2001220111021 has 4 divisors (see below), whose sum is σ = 2001362186592. Its totient is φ = 2001078035452.

The previous prime is 2001220110991. The next prime is 2001220111049. The reversal of 2001220111021 is 1201110221002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001220111021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001220110992 and 2001220111010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001220111061) 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, 71016655 + ... + 71044828.

It is an arithmetic number, because the mean of its divisors is an integer number (500340546648).

Almost surely, 2^{2001220111021} is an apocalyptic number.

It is an amenable number.

2001220111021 is a deficient number, since it is larger than the sum of its proper divisors (142075571).

2001220111021 is a wasteful number, since it uses less digits than its factorization.

2001220111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142075570.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 2001220111021 its reverse (1201110221002), we get a palindrome (3202330332023).

The spelling of 2001220111021 in words is "two trillion, one billion, two hundred twenty million, one hundred eleven thousand, twenty-one".