664838668472 has 192 divisors, whose sum is σ = 1453838284800. Its totient is φ = 282128295680.

The previous prime is 664838668463. The next prime is 664838668477. The reversal of 664838668472 is 274866838466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664838668477) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1387971929 + ... + 1387972407.

It is an arithmetic number, because the mean of its divisors is an integer number (7572074400).

Almost surely, 2^664838668472 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664838668472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (726919142400).

664838668472 is an abundant number, since it is smaller than the sum of its proper divisors (788999616328).

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

664838668472 is a wasteful number, since it uses less digits than its factorization.

664838668472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 834 (or 771 counting only the distinct ones).

The product of its digits is 445906944, while the sum is 68.

The spelling of 664838668472 in words is "six hundred sixty-four billion, eight hundred thirty-eight million, six hundred sixty-eight thousand, four hundred seventy-two".