664331 has 2 divisors, whose sum is σ = 664332. Its totient is φ = 664330.

The previous prime is 664319. The next prime is 664357. The reversal of 664331 is 133466.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664331 is a prime.

It is a super-2 number, since 2×664331² = 882671355122, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 9.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 664297 and 664306.

It is not a weakly prime, because it can be changed into another prime (664381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332165 + 332166.

It is an arithmetic number, because the mean of its divisors is an integer number (332166).

2⁶⁶⁴³³¹ is an apocalyptic number.

664331 is a deficient number, since it is larger than the sum of its proper divisors (1).

664331 is an equidigital number, since it uses as much as digits as its factorization.

664331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 23.

The square root of 664331 is about 815.0650280806. The cubic root of 664331 is about 87.2559074606.

Adding to 664331 its reverse (133466), we get a palindrome (797797).

The spelling of 664331 in words is "six hundred sixty-four thousand, three hundred thirty-one".