666471970647 has 32 divisors (see below), whose sum is σ = 1128458777600. Its totient is φ = 380827414944.

The previous prime is 666471970627. The next prime is 666471970667. The reversal of 666471970647 is 746079174666.

It is an interprime number because it is at equal distance from previous prime (666471970627) and next prime (666471970667).

It is not a de Polignac number, because 666471970647 - 2⁷ = 666471970519 is a prime.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666471970627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7714929 + ... + 7800837.

It is an arithmetic number, because the mean of its divisors is an integer number (35264336800).

Almost surely, 2^666471970647 is an apocalyptic number.

666471970647 is a deficient number, since it is larger than the sum of its proper divisors (461986806953).

666471970647 is a wasteful number, since it uses less digits than its factorization.

666471970647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126972 (or 126966 counting only the distinct ones).

The product of its (nonzero) digits is 64012032, while the sum is 63.

The spelling of 666471970647 in words is "six hundred sixty-six billion, four hundred seventy-one million, nine hundred seventy thousand, six hundred forty-seven".