665763823 has 2 divisors, whose sum is σ = 665763824. Its totient is φ = 665763822.

The previous prime is 665763811. The next prime is 665763851. The reversal of 665763823 is 328367566.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665763823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665793823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332881911 + 332881912.

It is an arithmetic number, because the mean of its divisors is an integer number (332881912).

Almost surely, 2^665763823 is an apocalyptic number.

665763823 is a deficient number, since it is larger than the sum of its proper divisors (1).

665763823 is an equidigital number, since it uses as much as digits as its factorization.

665763823 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 46.

The square root of 665763823 is about 25802.3995589558. The cubic root of 665763823 is about 873.1859332876.

The spelling of 665763823 in words is "six hundred sixty-five million, seven hundred sixty-three thousand, eight hundred twenty-three".