665617067117 has 4 divisors (see below), whose sum is σ = 665649105660. Its totient is φ = 665585028576.

The previous prime is 665617067113. The next prime is 665617067119. The reversal of 665617067117 is 711760716566.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 309374013796 + 356243053321 = 556214^2 + 596861^2 .

It is a cyclic number.

It is not a de Polignac number, because 665617067117 - 2² = 665617067113 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665617067113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15988088 + ... + 16029665.

It is an arithmetic number, because the mean of its divisors is an integer number (166412276415).

Almost surely, 2^665617067117 is an apocalyptic number.

It is an amenable number.

665617067117 is a deficient number, since it is larger than the sum of its proper divisors (32038543).

665617067117 is a wasteful number, since it uses less digits than its factorization.

665617067117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32038542.

The product of its (nonzero) digits is 2222640, while the sum is 53.

The spelling of 665617067117 in words is "six hundred sixty-five billion, six hundred seventeen million, sixty-seven thousand, one hundred seventeen".