671566871 has 4 divisors (see below), whose sum is σ = 671667000. Its totient is φ = 671466744.

The previous prime is 671566829. The next prime is 671566933. The reversal of 671566871 is 178665176.

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 671566871 - 2¹⁴ = 671550487 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 (671566171) 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, 39221 + ... + 53678.

It is an arithmetic number, because the mean of its divisors is an integer number (167916750).

Almost surely, 2^671566871 is an apocalyptic number.

671566871 is a deficient number, since it is larger than the sum of its proper divisors (100129).

671566871 is an equidigital number, since it uses as much as digits as its factorization.

671566871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100128.

The product of its digits is 423360, while the sum is 47.

The square root of 671566871 is about 25914.6072900980. The cubic root of 671566871 is about 875.7156033316.

The spelling of 671566871 in words is "six hundred seventy-one million, five hundred sixty-six thousand, eight hundred seventy-one".