2001221021213 has 2 divisors, whose sum is σ = 2001221021214. Its totient is φ = 2001221021212.

The previous prime is 2001221021179. The next prime is 2001221021243. The reversal of 2001221021213 is 3121201221002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1364324449849 + 636896571364 = 1168043^2 + 798058^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001221021213 - 2²⁶ = 2001153912349 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2001221021191 and 2001221021200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221021243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610510606 + 1000610510607.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610510607).

Almost surely, 2^{2001221021213} is an apocalyptic number.

It is an amenable number.

2001221021213 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221021213 is an equidigital number, since it uses as much as digits as its factorization.

2001221021213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 2001221021213 its reverse (3121201221002), we get a palindrome (5122422242215).

The spelling of 2001221021213 in words is "two trillion, one billion, two hundred twenty-one million, twenty-one thousand, two hundred thirteen".