665677671 has 4 divisors (see below), whose sum is σ = 887570232. Its totient is φ = 443785112.

The previous prime is 665677643. The next prime is 665677697. The reversal of 665677671 is 176776566.

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 665677671 - 2⁷ = 665677543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665677631) 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, 110946276 + ... + 110946281.

It is an arithmetic number, because the mean of its divisors is an integer number (221892558).

Almost surely, 2^665677671 is an apocalyptic number.

665677671 is a deficient number, since it is larger than the sum of its proper divisors (221892561).

665677671 is a wasteful number, since it uses less digits than its factorization.

665677671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221892560.

The product of its digits is 2222640, while the sum is 51.

The square root of 665677671 is about 25800.7300478107. The cubic root of 665677671 is about 873.1482672980.

The spelling of 665677671 in words is "six hundred sixty-five million, six hundred seventy-seven thousand, six hundred seventy-one".