2001222020221 has 4 divisors (see below), whose sum is σ = 2028636020572. Its totient is φ = 1973808019872.

The previous prime is 2001222020207. The next prime is 2001222020233. The reversal of 2001222020221 is 1220202221002.

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 419274380196 + 1581947640025 = 647514^2 + 1257755^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001222020221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001222020195 and 2001222020204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001222020321) 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, 13707000066 + ... + 13707000211.

It is an arithmetic number, because the mean of its divisors is an integer number (507159005143).

Almost surely, 2^{2001222020221} is an apocalyptic number.

It is an amenable number.

2001222020221 is a deficient number, since it is larger than the sum of its proper divisors (27414000351).

2001222020221 is an equidigital number, since it uses as much as digits as its factorization.

2001222020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27414000350.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 2001222020221 its reverse (1220202221002), we get a palindrome (3221424241223).

The spelling of 2001222020221 in words is "two trillion, one billion, two hundred twenty-two million, twenty thousand, two hundred twenty-one".