331020121021 has 4 divisors (see below), whose sum is σ = 336446680444. Its totient is φ = 325593561600.

The previous prime is 331020120997. The next prime is 331020121063. The reversal of 331020121021 is 120121020133.

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 179123632900 + 151896488121 = 423230^2 + 389739^2 .

It is a cyclic number.

It is not a de Polignac number, because 331020121021 - 2²⁹ = 330483250109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 331020120986 and 331020121004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331020121121) 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, 2713279620 + ... + 2713279741.

It is an arithmetic number, because the mean of its divisors is an integer number (84111670111).

Almost surely, 2^331020121021 is an apocalyptic number.

It is an amenable number.

331020121021 is a deficient number, since it is larger than the sum of its proper divisors (5426559423).

331020121021 is an equidigital number, since it uses as much as digits as its factorization.

331020121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5426559422.

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

Adding to 331020121021 its reverse (120121020133), we get a palindrome (451141141154).

The spelling of 331020121021 in words is "three hundred thirty-one billion, twenty million, one hundred twenty-one thousand, twenty-one".