664887157684 has 12 divisors (see below), whose sum is σ = 1172045611044. Its totient is φ = 330016983104.

The previous prime is 664887157673. The next prime is 664887157747. The reversal of 664887157684 is 486751788466.

It can be written as a sum of positive squares in 2 ways, for example, as 348111800100 + 316775357584 = 590010^2 + 562828^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 606648319 + ... + 606649414.

It is an arithmetic number, because the mean of its divisors is an integer number (97670467587).

Almost surely, 2^664887157684 is an apocalyptic number.

It is an amenable number.

664887157684 is a deficient number, since it is larger than the sum of its proper divisors (507158453360).

664887157684 is a wasteful number, since it uses less digits than its factorization.

664887157684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1213297874 (or 1213297872 counting only the distinct ones).

The product of its digits is 433520640, while the sum is 70.

The spelling of 664887157684 in words is "six hundred sixty-four billion, eight hundred eighty-seven million, one hundred fifty-seven thousand, six hundred eighty-four".