668505353 has 2 divisors, whose sum is σ = 668505354. Its totient is φ = 668505352.

The previous prime is 668505319. The next prime is 668505371. The reversal of 668505353 is 353505866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 635695369 + 32809984 = 25213^2 + 5728^2 .

It is a cyclic number.

It is not a de Polignac number, because 668505353 - 2⁶ = 668505289 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 668505353.

It is not a weakly prime, because it can be changed into another prime (668505053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334252676 + 334252677.

It is an arithmetic number, because the mean of its divisors is an integer number (334252677).

Almost surely, 2^668505353 is an apocalyptic number.

It is an amenable number.

668505353 is a deficient number, since it is larger than the sum of its proper divisors (1).

668505353 is an equidigital number, since it uses as much as digits as its factorization.

668505353 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324000, while the sum is 41.

The square root of 668505353 is about 25855.4704656481. The cubic root of 668505353 is about 874.3828477532.

The spelling of 668505353 in words is "six hundred sixty-eight million, five hundred five thousand, three hundred fifty-three".