665630993 has 2 divisors, whose sum is σ = 665630994. Its totient is φ = 665630992.

The previous prime is 665630981. The next prime is 665631067. The reversal of 665630993 is 399036566.

It is a happy number.

665630993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 588402049 + 77228944 = 24257^2 + 8788^2 .

It is a cyclic number.

It is not a de Polignac number, because 665630993 - 2¹⁰ = 665629969 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (665630923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332815496 + 332815497.

It is an arithmetic number, because the mean of its divisors is an integer number (332815497).

Almost surely, 2^665630993 is an apocalyptic number.

It is an amenable number.

665630993 is a deficient number, since it is larger than the sum of its proper divisors (1).

665630993 is an equidigital number, since it uses as much as digits as its factorization.

665630993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 787320, while the sum is 47.

The square root of 665630993 is about 25799.8254451459. The cubic root of 665630993 is about 873.1278581374.

The spelling of 665630993 in words is "six hundred sixty-five million, six hundred thirty thousand, nine hundred ninety-three".