665711679 has 8 divisors (see below), whose sum is σ = 896766640. Its totient is φ = 439232256.

The previous prime is 665711677. The next prime is 665711699. The reversal of 665711679 is 976117566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 665711679 - 2¹ = 665711677 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 (665711677) 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, 1143544 + ... + 1144125.

It is an arithmetic number, because the mean of its divisors is an integer number (112095830).

Almost surely, 2^665711679 is an apocalyptic number.

665711679 is a deficient number, since it is larger than the sum of its proper divisors (231054961).

665711679 is a wasteful number, since it uses less digits than its factorization.

665711679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2287769.

The product of its digits is 476280, while the sum is 48.

The square root of 665711679 is about 25801.3890905122. The cubic root of 665711679 is about 873.1631361161.

It can be divided in two parts, 6657 and 11679, that added together give a triangular number (18336 = T₁₉₁).

The spelling of 665711679 in words is "six hundred sixty-five million, seven hundred eleven thousand, six hundred seventy-nine".