669709671 has 4 divisors (see below), whose sum is σ = 892946232. Its totient is φ = 446473112.

The previous prime is 669709669. The next prime is 669709687. The reversal of 669709671 is 176907966.

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 669709671 - 2¹ = 669709669 is a prime.

It is a super-2 number, since 2×669709671² = 897022086861856482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669709661) 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, 111618276 + ... + 111618281.

It is an arithmetic number, because the mean of its divisors is an integer number (223236558).

Almost surely, 2^669709671 is an apocalyptic number.

669709671 is a deficient number, since it is larger than the sum of its proper divisors (223236561).

669709671 is a wasteful number, since it uses less digits than its factorization.

669709671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223236560.

The product of its (nonzero) digits is 857304, while the sum is 51.

The square root of 669709671 is about 25878.7494095059. The cubic root of 669709671 is about 874.9076021073.

The spelling of 669709671 in words is "six hundred sixty-nine million, seven hundred nine thousand, six hundred seventy-one".