665647386 has 16 divisors (see below), whose sum is σ = 1341778944. Its totient is φ = 220135104.

The previous prime is 665647379. The next prime is 665647399. The reversal of 665647386 is 683746566.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 436015 + ... + 437538.

It is an arithmetic number, because the mean of its divisors is an integer number (83861184).

Almost surely, 2^665647386 is an apocalyptic number.

665647386 is an abundant number, since it is smaller than the sum of its proper divisors (676131558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665647386 is a wasteful number, since it uses less digits than its factorization.

665647386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873685.

The product of its digits is 4354560, while the sum is 51.

The square root of 665647386 is about 25800.1431391378. The cubic root of 665647386 is about 873.1350258062.

The spelling of 665647386 in words is "six hundred sixty-five million, six hundred forty-seven thousand, three hundred eighty-six".