666518671 has 8 divisors (see below), whose sum is σ = 820330784. Its totient is φ = 527355360.

The previous prime is 666518663. The next prime is 666518683. The reversal of 666518671 is 176815666.

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

It is not a de Polignac number, because 666518671 - 2³ = 666518663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666518471) 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, 3662100 + ... + 3662281.

It is an arithmetic number, because the mean of its divisors is an integer number (102541348).

Almost surely, 2^666518671 is an apocalyptic number.

666518671 is a deficient number, since it is larger than the sum of its proper divisors (153812113).

666518671 is a wasteful number, since it uses less digits than its factorization.

666518671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7324401.

The product of its digits is 362880, while the sum is 46.

The square root of 666518671 is about 25817.0228918828. The cubic root of 666518671 is about 873.5158168906.

The spelling of 666518671 in words is "six hundred sixty-six million, five hundred eighteen thousand, six hundred seventy-one".