665147180865 has 64 divisors (see below), whose sum is σ = 1105539240960. Its totient is φ = 341081798400.

The previous prime is 665147180861. The next prime is 665147180891. The reversal of 665147180865 is 568081741566.

It is not a de Polignac number, because 665147180865 - 2² = 665147180861 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (665147180861) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 233301690 + ... + 233304540.

It is an arithmetic number, because the mean of its divisors is an integer number (17274050640).

Almost surely, 2^665147180865 is an apocalyptic number.

It is an amenable number.

665147180865 is a deficient number, since it is larger than the sum of its proper divisors (440392060095).

665147180865 is a wasteful number, since it uses less digits than its factorization.

665147180865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4942.

The product of its (nonzero) digits is 9676800, while the sum is 57.

The spelling of 665147180865 in words is "six hundred sixty-five billion, one hundred forty-seven million, one hundred eighty thousand, eight hundred sixty-five".