664821514808 has 16 divisors (see below), whose sum is σ = 1359862189560. Its totient is φ = 302191597600.

The previous prime is 664821514787. The next prime is 664821514831. The reversal of 664821514808 is 808415128466.

It is a self number, because there is not a number n which added to its sum of digits gives 664821514808.

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, 3777394883 + ... + 3777395058.

Almost surely, 2^664821514808 is an apocalyptic number.

It is an amenable number.

664821514808 is an abundant number, since it is smaller than the sum of its proper divisors (695040674752).

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

664821514808 is a wasteful number, since it uses less digits than its factorization.

664821514808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7554789958 (or 7554789954 counting only the distinct ones).

The product of its (nonzero) digits is 2949120, while the sum is 53.

The spelling of 664821514808 in words is "six hundred sixty-four billion, eight hundred twenty-one million, five hundred fourteen thousand, eight hundred eight".