664978137858 has 48 divisors (see below), whose sum is σ = 1443091923000. Its totient is φ = 221304902400.

The previous prime is 664978137853. The next prime is 664978137871. The reversal of 664978137858 is 858731879466.

664978137858 is a `hidden beast` number, since 6 + 6 + 497 + 8 + 13 + 78 + 58 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 614165313969 + 50812823889 = 783687^2 + 225417^2 .

It is not an unprimeable number, because it can be changed into a prime (664978137853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31503508 + ... + 31524608.

Almost surely, 2^664978137858 is an apocalyptic number.

664978137858 is an abundant number, since it is smaller than the sum of its proper divisors (778113785142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664978137858 is a wasteful number, since it uses less digits than its factorization.

664978137858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23827 (or 23824 counting only the distinct ones).

The product of its digits is 487710720, while the sum is 72.

The spelling of 664978137858 in words is "six hundred sixty-four billion, nine hundred seventy-eight million, one hundred thirty-seven thousand, eight hundred fifty-eight".