2001200121001 has 4 divisors (see below), whose sum is σ = 2001240628992. Its totient is φ = 2001159613012.

The previous prime is 2001200120989. The next prime is 2001200121007. The reversal of 2001200121001 is 1001210021002.

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-2001200121001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2001200121007) 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 3 ways as a sum of consecutive naturals, for example, 20179801 + ... + 20278726.

It is an arithmetic number, because the mean of its divisors is an integer number (500310157248).

Almost surely, 2^{2001200121001} is an apocalyptic number.

It is an amenable number.

2001200121001 is a deficient number, since it is larger than the sum of its proper divisors (40507991).

2001200121001 is an equidigital number, since it uses as much as digits as its factorization.

2001200121001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40507990.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 2001200121001 its reverse (1001210021002), we get a palindrome (3002410142003).

Subtracting from 2001200121001 its reverse (1001210021002), we obtain a palindrome (999990099999).

It can be divided in two parts, 20012001 and 21001, that added together give a palindrome (20033002).

The spelling of 2001200121001 in words is "two trillion, one billion, two hundred million, one hundred twenty-one thousand, one".