2001020202221 has 4 divisors (see below), whose sum is σ = 2001023714172. Its totient is φ = 2001016690272.

The previous prime is 2001020202217. The next prime is 2001020202277. The reversal of 2001020202221 is 1222020201002.

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 611719515625 + 1389300686596 = 782125^2 + 1178686^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001020202221 - 2² = 2001020202217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001020202196 and 2001020202205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001020202281) 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, 682610 + ... + 2113763.

It is an arithmetic number, because the mean of its divisors is an integer number (500255928543).

Almost surely, 2^{2001020202221} is an apocalyptic number.

It is an amenable number.

2001020202221 is a deficient number, since it is larger than the sum of its proper divisors (3511951).

2001020202221 is an equidigital number, since it uses as much as digits as its factorization.

2001020202221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3511950.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 2001020202221 its reverse (1222020201002), we get a palindrome (3223040403223).

The spelling of 2001020202221 in words is "two trillion, one billion, twenty million, two hundred two thousand, two hundred twenty-one".