665566239 has 8 divisors (see below), whose sum is σ = 955684912. Its totient is φ = 409579200.

The previous prime is 665566229. The next prime is 665566259. The reversal of 665566239 is 932665566.

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

It is not a de Polignac number, because 665566239 - 2⁵ = 665566207 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665566229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8532862 + ... + 8532939.

It is an arithmetic number, because the mean of its divisors is an integer number (119460614).

Almost surely, 2^665566239 is an apocalyptic number.

665566239 is a deficient number, since it is larger than the sum of its proper divisors (290118673).

665566239 is a wasteful number, since it uses less digits than its factorization.

665566239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17065817.

The product of its digits is 1749600, while the sum is 48.

The square root of 665566239 is about 25798.5704836528. The cubic root of 665566239 is about 873.0995439737.

The spelling of 665566239 in words is "six hundred sixty-five million, five hundred sixty-six thousand, two hundred thirty-nine".