664026331 has 2 divisors, whose sum is σ = 664026332. Its totient is φ = 664026330.

The previous prime is 664026317. The next prime is 664026361. The reversal of 664026331 is 133620466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664026331 - 2⁵ = 664026299 is a prime.

It is a super-2 number, since 2×664026331² = 881861936522643122, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 664026293 and 664026302.

It is not a weakly prime, because it can be changed into another prime (664026301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332013165 + 332013166.

It is an arithmetic number, because the mean of its divisors is an integer number (332013166).

Almost surely, 2^664026331 is an apocalyptic number.

664026331 is a deficient number, since it is larger than the sum of its proper divisors (1).

664026331 is an equidigital number, since it uses as much as digits as its factorization.

664026331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 664026331 is about 25768.7083688725. The cubic root of 664026331 is about 872.4256660344.

Adding to 664026331 its reverse (133620466), we get a palindrome (797646797).

The spelling of 664026331 in words is "six hundred sixty-four million, twenty-six thousand, three hundred thirty-one".