664683839 has 2 divisors, whose sum is σ = 664683840. Its totient is φ = 664683838.

The previous prime is 664683829. The next prime is 664683847. The reversal of 664683839 is 938386466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664683839 - 2²⁰ = 663635263 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664683829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332341919 + 332341920.

It is an arithmetic number, because the mean of its divisors is an integer number (332341920).

Almost surely, 2^664683839 is an apocalyptic number.

664683839 is a deficient number, since it is larger than the sum of its proper divisors (1).

664683839 is an equidigital number, since it uses as much as digits as its factorization.

664683839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4478976, while the sum is 53.

The square root of 664683839 is about 25781.4630888164. The cubic root of 664683839 is about 872.7135249140.

It can be divided in two parts, 66468 and 3839, that added together give a palindrome (70307).

The spelling of 664683839 in words is "six hundred sixty-four million, six hundred eighty-three thousand, eight hundred thirty-nine".