331313021 has 16 divisors (see below), whose sum is σ = 366070320. Its totient is φ = 297976320.

The previous prime is 331312987. The next prime is 331313039. The reversal of 331313021 is 120313133.

It can be written as a sum of positive squares in 8 ways, for example, as 89510521 + 241802500 = 9461^2 + 15550^2 .

It is a cyclic number.

It is not a de Polignac number, because 331313021 - 2⁶ = 331312957 is a prime.

It is a super-4 number, since 4×331313021⁴ (a number of 35 digits) contains 4444 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331313071) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84521 + ... + 88353.

It is an arithmetic number, because the mean of its divisors is an integer number (22879395).

Almost surely, 2^331313021 is an apocalyptic number.

It is an amenable number.

331313021 is a deficient number, since it is larger than the sum of its proper divisors (34757299).

331313021 is a wasteful number, since it uses less digits than its factorization.

331313021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4016.

The product of its (nonzero) digits is 162, while the sum is 17.

The square root of 331313021 is about 18202.0059608824. The cubic root of 331313021 is about 691.9576283823.

Adding to 331313021 its reverse (120313133), we get a palindrome (451626154).

The spelling of 331313021 in words is "three hundred thirty-one million, three hundred thirteen thousand, twenty-one".