664838787808 has 24 divisors (see below), whose sum is σ = 1409586084648. Its totient is φ = 306848671104.

The previous prime is 664838787799. The next prime is 664838787853. The reversal of 664838787808 is 808787838466.

It is a super-2 number, since 2×664838787808² (a number of 24 digits) contains 22 as substring.

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, 799084666 + ... + 799085497.

It is an arithmetic number, because the mean of its divisors is an integer number (58732753527).

Almost surely, 2^664838787808 is an apocalyptic number.

It is an amenable number.

664838787808 is an abundant number, since it is smaller than the sum of its proper divisors (744747296840).

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

664838787808 is a wasteful number, since it uses less digits than its factorization.

664838787808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1598170186 (or 1598170178 counting only the distinct ones).

The product of its (nonzero) digits is 693633024, while the sum is 73.

The spelling of 664838787808 in words is "six hundred sixty-four billion, eight hundred thirty-eight million, seven hundred eighty-seven thousand, eight hundred eight".