2001311222221 has 4 divisors (see below), whose sum is σ = 2047853343712. Its totient is φ = 1954769100732.

The previous prime is 2001311222219. The next prime is 2001311222227. The reversal of 2001311222221 is 1222221131002.

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 2001311222221 - 2¹ = 2001311222219 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 (2001311222227) 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, 23271060681 + ... + 23271060766.

It is an arithmetic number, because the mean of its divisors is an integer number (511963335928).

Almost surely, 2^{2001311222221} is an apocalyptic number.

It is an amenable number.

2001311222221 is a deficient number, since it is larger than the sum of its proper divisors (46542121491).

2001311222221 is an equidigital number, since it uses as much as digits as its factorization.

2001311222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46542121490.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 2001311222221 its reverse (1222221131002), we get a palindrome (3223532353223).

The spelling of 2001311222221 in words is "two trillion, one billion, three hundred eleven million, two hundred twenty-two thousand, two hundred twenty-one".