666064667 has 4 divisors (see below), whose sum is σ = 687550656. Its totient is φ = 644578680.

The previous prime is 666064631. The next prime is 666064669. The reversal of 666064667 is 766460666.

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

It is a cyclic number.

It is not a de Polignac number, because 666064667 - 2²⁰ = 665016091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666064669) 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, 10742948 + ... + 10743009.

It is an arithmetic number, because the mean of its divisors is an integer number (171887664).

Almost surely, 2^666064667 is an apocalyptic number.

666064667 is a deficient number, since it is larger than the sum of its proper divisors (21485989).

666064667 is a wasteful number, since it uses less digits than its factorization.

666064667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21485988.

The product of its (nonzero) digits is 1306368, while the sum is 47.

The square root of 666064667 is about 25808.2286683918. The cubic root of 666064667 is about 873.3174379751.

The spelling of 666064667 in words is "six hundred sixty-six million, sixty-four thousand, six hundred sixty-seven".