665434788377 has 2 divisors, whose sum is σ = 665434788378. Its totient is φ = 665434788376.

The previous prime is 665434788301. The next prime is 665434788379. The reversal of 665434788377 is 773887434566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 526983076096 + 138451712281 = 725936^2 + 372091^2 .

It is a cyclic number.

It is not a de Polignac number, because 665434788377 - 2²⁴ = 665418011161 is a prime.

Together with 665434788379, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (665434788379) 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, 332717394188 + 332717394189.

It is an arithmetic number, because the mean of its divisors is an integer number (332717394189).

Almost surely, 2^665434788377 is an apocalyptic number.

It is an amenable number.

665434788377 is a deficient number, since it is larger than the sum of its proper divisors (1).

665434788377 is an equidigital number, since it uses as much as digits as its factorization.

665434788377 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 568995840, while the sum is 68.

The spelling of 665434788377 in words is "six hundred sixty-five billion, four hundred thirty-four million, seven hundred eighty-eight thousand, three hundred seventy-seven".