331020013021 has 4 divisors (see below), whose sum is σ = 334739339100. Its totient is φ = 327300686944.

The previous prime is 331020013001. The next prime is 331020013039. The reversal of 331020013021 is 120310020133.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120310020133 = 1637 ⋅73494209.

It can be written as a sum of positive squares in 2 ways, for example, as 56365407396 + 274654605625 = 237414^2 + 524075^2 .

It is a cyclic number.

It is not a de Polignac number, because 331020013021 - 2⁵ = 331020012989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 331020012986 and 331020013004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331020013001) 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, 1859662906 + ... + 1859663083.

It is an arithmetic number, because the mean of its divisors is an integer number (83684834775).

Almost surely, 2^331020013021 is an apocalyptic number.

It is an amenable number.

331020013021 is a deficient number, since it is larger than the sum of its proper divisors (3719326079).

331020013021 is an equidigital number, since it uses as much as digits as its factorization.

331020013021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3719326078.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 331020013021 its reverse (120310020133), we get a palindrome (451330033154).

The spelling of 331020013021 in words is "three hundred thirty-one billion, twenty million, thirteen thousand, twenty-one".