2001112211221 has 8 divisors (see below), whose sum is σ = 2118851953560. Its totient is φ = 1883375497728.

The previous prime is 2001112211123. The next prime is 2001112211233. The reversal of 2001112211221 is 1221122111002.

It can be written as a sum of positive squares in 4 ways, for example, as 951278362225 + 1049833848996 = 975335^2 + 1024614^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2001112211221 - 2²⁵ = 2001078656789 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001112211195 and 2001112211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001112211321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 681105 + ... + 2113321.

It is an arithmetic number, because the mean of its divisors is an integer number (264856494195).

Almost surely, 2^{2001112211221} is an apocalyptic number.

It is an amenable number.

2001112211221 is a deficient number, since it is larger than the sum of its proper divisors (117739742339).

2001112211221 is a wasteful number, since it uses less digits than its factorization.

2001112211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1514423.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 2001112211221 its reverse (1221122111002), we get a palindrome (3222234322223).

The spelling of 2001112211221 in words is "two trillion, one billion, one hundred twelve million, two hundred eleven thousand, two hundred twenty-one".