666471898856 has 8 divisors (see below), whose sum is σ = 1249634810370. Its totient is φ = 333235949424.

The previous prime is 666471898843. The next prime is 666471898871. The reversal of 666471898856 is 658898174666.

666471898856 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 488922592900 + 177549305956 = 699230^2 + 421366^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41654493671 + ... + 41654493686.

Almost surely, 2^666471898856 is an apocalyptic number.

It is an amenable number.

666471898856 is a deficient number, since it is larger than the sum of its proper divisors (583162911514).

666471898856 is a wasteful number, since it uses less digits than its factorization.

666471898856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83308987363 (or 83308987359 counting only the distinct ones).

The product of its digits is 836075520, while the sum is 74.

The spelling of 666471898856 in words is "six hundred sixty-six billion, four hundred seventy-one million, eight hundred ninety-eight thousand, eight hundred fifty-six".