664675261671 has 24 divisors (see below), whose sum is σ = 935576431104. Its totient is φ = 419685423120.

The previous prime is 664675261667. The next prime is 664675261673. The reversal of 664675261671 is 176162576466.

It is not a de Polignac number, because 664675261671 - 2² = 664675261667 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664675261673) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 4179210 + ... + 4335336.

It is an arithmetic number, because the mean of its divisors is an integer number (38982351296).

Almost surely, 2^664675261671 is an apocalyptic number.

664675261671 is a deficient number, since it is larger than the sum of its proper divisors (270901169433).

664675261671 is a wasteful number, since it uses less digits than its factorization.

664675261671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160099 (or 160080 counting only the distinct ones).

The product of its digits is 15240960, while the sum is 57.

The spelling of 664675261671 in words is "six hundred sixty-four billion, six hundred seventy-five million, two hundred sixty-one thousand, six hundred seventy-one".