667866957871 has 8 divisors (see below), whose sum is σ = 690908194080. Its totient is φ = 644826477792.

The previous prime is 667866957869. The next prime is 667866957881. The reversal of 667866957871 is 178759668766.

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 667866957871 - 2¹ = 667866957869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667866957881) 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, 2062806 + ... + 2364508.

It is an arithmetic number, because the mean of its divisors is an integer number (86363524260).

Almost surely, 2^667866957871 is an apocalyptic number.

667866957871 is a deficient number, since it is larger than the sum of its proper divisors (23041236209).

667866957871 is a wasteful number, since it uses less digits than its factorization.

667866957871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378065.

The product of its digits is 1280240640, while the sum is 76.

The spelling of 667866957871 in words is "six hundred sixty-seven billion, eight hundred sixty-six million, nine hundred fifty-seven thousand, eight hundred seventy-one".