665345543566 has 32 divisors (see below), whose sum is σ = 1090030066560. Its totient is φ = 302073688800.

The previous prime is 665345543531. The next prime is 665345543581.

665345543566 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 665345543566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89774401 + ... + 89781811.

It is an arithmetic number, because the mean of its divisors is an integer number (34063439580).

Almost surely, 2^665345543566 is an apocalyptic number.

665345543566 is a deficient number, since it is larger than the sum of its proper divisors (424684522994).

665345543566 is a wasteful number, since it uses less digits than its factorization.

665345543566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11680.

The product of its digits is 116640000, while the sum is 58.

The spelling of 665345543566 in words is "six hundred sixty-five billion, three hundred forty-five million, five hundred forty-three thousand, five hundred sixty-six".