665610653 has 2 divisors, whose sum is σ = 665610654. Its totient is φ = 665610652.

The previous prime is 665610637. The next prime is 665610661. The reversal of 665610653 is 356016566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 463885444 + 201725209 = 21538^2 + 14203^2 .

It is a cyclic number.

It is not a de Polignac number, because 665610653 - 2⁴ = 665610637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665610853) 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, 332805326 + 332805327.

It is an arithmetic number, because the mean of its divisors is an integer number (332805327).

Almost surely, 2^665610653 is an apocalyptic number.

It is an amenable number.

665610653 is a deficient number, since it is larger than the sum of its proper divisors (1).

665610653 is an equidigital number, since it uses as much as digits as its factorization.

665610653 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 97200, while the sum is 38.

The square root of 665610653 is about 25799.4312534211. The cubic root of 665610653 is about 873.1189645203.

The spelling of 665610653 in words is "six hundred sixty-five million, six hundred ten thousand, six hundred fifty-three".