665173371566 has 64 divisors (see below), whose sum is σ = 1108121236992. Its totient is φ = 296946000000.

The previous prime is 665173371559. The next prime is 665173371571.

665173371566 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×665173371566² (a number of 24 digits) contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 392895416 + ... + 392897108.

It is an arithmetic number, because the mean of its divisors is an integer number (17314394328).

Almost surely, 2^665173371566 is an apocalyptic number.

665173371566 is a deficient number, since it is larger than the sum of its proper divisors (442947865426).

665173371566 is a wasteful number, since it uses less digits than its factorization.

665173371566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3129.

The product of its digits is 14288400, while the sum is 56.

The spelling of 665173371566 in words is "six hundred sixty-five billion, one hundred seventy-three million, three hundred seventy-one thousand, five hundred sixty-six".