665070607321 has 2 divisors, whose sum is σ = 665070607322. Its totient is φ = 665070607320.

The previous prime is 665070607213. The next prime is 665070607403. The reversal of 665070607321 is 123706070566.

Together with previous prime (665070607213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 633265808400 + 31804798921 = 795780^2 + 178339^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665070607321 is a prime.

It is not a weakly prime, because it can be changed into another prime (665070602321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332535303660 + 332535303661.

It is an arithmetic number, because the mean of its divisors is an integer number (332535303661).

Almost surely, 2^665070607321 is an apocalyptic number.

It is an amenable number.

665070607321 is a deficient number, since it is larger than the sum of its proper divisors (1).

665070607321 is an equidigital number, since it uses as much as digits as its factorization.

665070607321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 317520, while the sum is 43.

Adding to 665070607321 its reverse (123706070566), we get a palindrome (788776677887).

The spelling of 665070607321 in words is "six hundred sixty-five billion, seventy million, six hundred seven thousand, three hundred twenty-one".