665641163331 has 24 divisors (see below), whose sum is σ = 966429391200. Its totient is φ = 441477755136.

The previous prime is 665641163311. The next prime is 665641163353. The reversal of 665641163331 is 133361146566.

665641163331 is a `hidden beast` number, since 6 + 6 + 5 + 6 + 4 + 1 + 1 + 633 + 3 + 1 = 666.

It is not a de Polignac number, because 665641163331 - 2¹⁸ = 665640901187 is a prime.

It is a super-3 number, since 3×665641163331³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (665641163311) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19786281 + ... + 19819893.

It is an arithmetic number, because the mean of its divisors is an integer number (40267891300).

Almost surely, 2^665641163331 is an apocalyptic number.

665641163331 is a deficient number, since it is larger than the sum of its proper divisors (300788227869).

665641163331 is a wasteful number, since it uses less digits than its factorization.

665641163331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44875 (or 44872 counting only the distinct ones).

The product of its digits is 699840, while the sum is 45.

The spelling of 665641163331 in words is "six hundred sixty-five billion, six hundred forty-one million, one hundred sixty-three thousand, three hundred thirty-one".