665640760855 has 16 divisors (see below), whose sum is σ = 912904556544. Its totient is φ = 456426479520.

The previous prime is 665640760853. The next prime is 665640760859. The reversal of 665640760855 is 558067046566.

It is not a de Polignac number, because 665640760855 - 2¹ = 665640760853 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 665640760855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665640760853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1083210 + ... + 1582600.

It is an arithmetic number, because the mean of its divisors is an integer number (57056534784).

Almost surely, 2^665640760855 is an apocalyptic number.

665640760855 is a deficient number, since it is larger than the sum of its proper divisors (247263795689).

665640760855 is a wasteful number, since it uses less digits than its factorization.

665640760855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537486.

The product of its (nonzero) digits is 36288000, while the sum is 58.

The spelling of 665640760855 in words is "six hundred sixty-five billion, six hundred forty million, seven hundred sixty thousand, eight hundred fifty-five".