2001321002221 has 4 divisors (see below), whose sum is σ = 2001331858012. Its totient is φ = 2001310146432.

The previous prime is 2001321002203. The next prime is 2001321002243. The reversal of 2001321002221 is 1222001231002.

It is a happy number.

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 171756369225 + 1829564632996 = 414435^2 + 1352614^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001321002221 - 2⁹ = 2001321001709 is a prime.

It is a super-3 number, since 3×2001321002221³ (a number of 38 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001321002195 and 2001321002204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001321003221) 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, 5146500 + ... + 5521693.

It is an arithmetic number, because the mean of its divisors is an integer number (500332964503).

Almost surely, 2^{2001321002221} is an apocalyptic number.

It is an amenable number.

2001321002221 is a deficient number, since it is larger than the sum of its proper divisors (10855791).

2001321002221 is a wasteful number, since it uses less digits than its factorization.

2001321002221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10855790.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 2001321002221 its reverse (1222001231002), we get a palindrome (3223322233223).

The spelling of 2001321002221 in words is "two trillion, one billion, three hundred twenty-one million, two thousand, two hundred twenty-one".