12001331021 has 4 divisors (see below), whose sum is σ = 12001855932. Its totient is φ = 12000806112.

The previous prime is 12001331009. The next prime is 12001331039. The reversal of 12001331021 is 12013310021.

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 4663524100 + 7337806921 = 68290^2 + 85661^2 .

It is a cyclic number.

It is not a de Polignac number, because 12001331021 - 2¹⁰ = 12001329997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12001330987 and 12001331005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12001330021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226520 + ... + 274433.

It is an arithmetic number, because the mean of its divisors is an integer number (3000463983).

Almost surely, 2^12001331021 is an apocalyptic number.

It is an amenable number.

12001331021 is a deficient number, since it is larger than the sum of its proper divisors (524911).

12001331021 is an equidigital number, since it uses as much as digits as its factorization.

12001331021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524910.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 12001331021 its reverse (12013310021), we get a palindrome (24014641042).

The spelling of 12001331021 in words is "twelve billion, one million, three hundred thirty-one thousand, twenty-one".