667646700667 has 4 divisors (see below), whose sum is σ = 690669000720. Its totient is φ = 644624400616.

The previous prime is 667646700659. The next prime is 667646700671. The reversal of 667646700667 is 766007646766.

It is a happy number.

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 667646700667 - 2³ = 667646700659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667646790667) 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, 11511149983 + ... + 11511150040.

It is an arithmetic number, because the mean of its divisors is an integer number (172667250180).

Almost surely, 2^667646700667 is an apocalyptic number.

667646700667 is a deficient number, since it is larger than the sum of its proper divisors (23022300053).

667646700667 is a wasteful number, since it uses less digits than its factorization.

667646700667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23022300052.

The product of its (nonzero) digits is 64012032, while the sum is 61.

The spelling of 667646700667 in words is "six hundred sixty-seven billion, six hundred forty-six million, seven hundred thousand, six hundred sixty-seven".