665030081 has 2 divisors, whose sum is σ = 665030082. Its totient is φ = 665030080.

The previous prime is 665030063. The next prime is 665030083. The reversal of 665030081 is 180030566.

665030081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 656179456 + 8850625 = 25616^2 + 2975^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665030081 is a prime.

It is a super-2 number, since 2×665030081² = 884530017269733122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 665030083, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (665030083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332515040 + 332515041.

It is an arithmetic number, because the mean of its divisors is an integer number (332515041).

Almost surely, 2^665030081 is an apocalyptic number.

It is an amenable number.

665030081 is a deficient number, since it is larger than the sum of its proper divisors (1).

665030081 is an equidigital number, since it uses as much as digits as its factorization.

665030081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 665030081 is about 25788.1771554331. The cubic root of 665030081 is about 872.8650343513.

The spelling of 665030081 in words is "six hundred sixty-five million, thirty thousand, eighty-one".