2001231310021 has 4 divisors (see below), whose sum is σ = 2026563352000. Its totient is φ = 1975899268044.

The previous prime is 2001231310019. The next prime is 2001231310031. The reversal of 2001231310021 is 1200131321002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2001231310021 - 2¹ = 2001231310019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001231309977 and 2001231310004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001231310031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12666020871 + ... + 12666021028.

It is an arithmetic number, because the mean of its divisors is an integer number (506640838000).

Almost surely, 2^{2001231310021} is an apocalyptic number.

It is an amenable number.

2001231310021 is a deficient number, since it is larger than the sum of its proper divisors (25332041979).

2001231310021 is an equidigital number, since it uses as much as digits as its factorization.

2001231310021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25332041978.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 2001231310021 its reverse (1200131321002), we get a palindrome (3201362631023).

The spelling of 2001231310021 in words is "two trillion, one billion, two hundred thirty-one million, three hundred ten thousand, twenty-one".