665205817255 has 32 divisors (see below), whose sum is σ = 916799067648. Its totient is φ = 453883651200.

The previous prime is 665205817189. The next prime is 665205817333. The reversal of 665205817255 is 552718502566.

It is a de Polignac number, because none of the positive numbers 2^k-665205817255 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68978464 + ... + 68988106.

It is an arithmetic number, because the mean of its divisors is an integer number (28649970864).

Almost surely, 2^665205817255 is an apocalyptic number.

665205817255 is a deficient number, since it is larger than the sum of its proper divisors (251593250393).

665205817255 is a wasteful number, since it uses less digits than its factorization.

665205817255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19207.

The product of its (nonzero) digits is 5040000, while the sum is 52.

The spelling of 665205817255 in words is "six hundred sixty-five billion, two hundred five million, eight hundred seventeen thousand, two hundred fifty-five".