2001100011221 has 4 divisors (see below), whose sum is σ = 2023584281100. Its totient is φ = 1978615741344.

The previous prime is 2001100011217. The next prime is 2001100011259. The reversal of 2001100011221 is 1221100011002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 998620476100 + 1002479535121 = 999310^2 + 1001239^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001100011221 - 2² = 2001100011217 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 (2001100011121) 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, 11242134806 + ... + 11242134983.

It is an arithmetic number, because the mean of its divisors is an integer number (505896070275).

Almost surely, 2^{2001100011221} is an apocalyptic number.

It is an amenable number.

2001100011221 is a deficient number, since it is larger than the sum of its proper divisors (22484269879).

2001100011221 is an equidigital number, since it uses as much as digits as its factorization.

2001100011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22484269878.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 2001100011221 its reverse (1221100011002), we get a palindrome (3222200022223).

The spelling of 2001100011221 in words is "two trillion, one billion, one hundred million, eleven thousand, two hundred twenty-one".