666604617667 has 8 divisors (see below), whose sum is σ = 686624322560. Its totient is φ = 646790243400.

The previous prime is 666604617607. The next prime is 666604617673. The reversal of 666604617667 is 766716406666.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666604617667 - 2²³ = 666596229059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666604617607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51326067 + ... + 51339052.

It is an arithmetic number, because the mean of its divisors is an integer number (85828040320).

Almost surely, 2^666604617667 is an apocalyptic number.

666604617667 is a deficient number, since it is larger than the sum of its proper divisors (20019704893).

666604617667 is a wasteful number, since it uses less digits than its factorization.

666604617667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102665313.

The product of its (nonzero) digits is 54867456, while the sum is 61.

The spelling of 666604617667 in words is "six hundred sixty-six billion, six hundred four million, six hundred seventeen thousand, six hundred sixty-seven".