331010021 has 2 divisors, whose sum is σ = 331010022. Its totient is φ = 331010020.

The previous prime is 331010003. The next prime is 331010041. The reversal of 331010021 is 120010133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 329821921 + 1188100 = 18161^2 + 1090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-331010021 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 331009984 and 331010011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331010041) 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 as a sum of consecutive naturals, namely, 165505010 + 165505011.

It is an arithmetic number, because the mean of its divisors is an integer number (165505011).

Almost surely, 2^331010021 is an apocalyptic number.

It is an amenable number.

331010021 is a deficient number, since it is larger than the sum of its proper divisors (1).

331010021 is an equidigital number, since it uses as much as digits as its factorization.

331010021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 331010021 is about 18193.6807985630. The cubic root of 331010021 is about 691.7466223789.

Adding to 331010021 its reverse (120010133), we get a palindrome (451020154).

It can be divided in two parts, 3310 and 10021, that added together give a palindrome (13331).

The spelling of 331010021 in words is "three hundred thirty-one million, ten thousand, twenty-one".