2001001222221 has 4 divisors (see below), whose sum is σ = 2668001629632. Its totient is φ = 1334000814812.

The previous prime is 2001001222193. The next prime is 2001001222229. The reversal of 2001001222221 is 1222221001002.

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 not a de Polignac number, because 2001001222221 - 2³⁴ = 1983821353037 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2001001222221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001001222229) 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, 333500203701 + ... + 333500203706.

It is an arithmetic number, because the mean of its divisors is an integer number (667000407408).

Almost surely, 2^{2001001222221} is an apocalyptic number.

It is an amenable number.

2001001222221 is a deficient number, since it is larger than the sum of its proper divisors (667000407411).

2001001222221 is an equidigital number, since it uses as much as digits as its factorization.

2001001222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667000407410.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 2001001222221 its reverse (1222221001002), we get a palindrome (3223222223223).

It can be divided in two parts, 2001001 and 222221, that added together give a palindrome (2223222).

The spelling of 2001001222221 in words is "two trillion, one billion, one million, two hundred twenty-two thousand, two hundred twenty-one".