664800017634560 has 144 divisors (see below), whose sum is σ = 1618555518316800. Its totient is φ = 261577883394048.

The previous prime is 664800017634553. The next prime is 664800017634581. The reversal of 664800017634560 is 65436710008466.

It is a super-2 number, since 2×664800017634560² (a number of 30 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 664800017634496 and 664800017634505.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14981267 + ... + 39421293.

It is an arithmetic number, because the mean of its divisors is an integer number (11239968877200).

Almost surely, 2^{664800017634560} 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 664800017634560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (809277759158400).

664800017634560 is an abundant number, since it is smaller than the sum of its proper divisors (953755500682240).

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

664800017634560 is a wasteful number, since it uses less digits than its factorization.

664800017634560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24440396 (or 24440382 counting only the distinct ones).

The product of its (nonzero) digits is 17418240, while the sum is 56.

The spelling of 664800017634560 in words is "six hundred sixty-four trillion, eight hundred billion, seventeen million, six hundred thirty-four thousand, five hundred sixty".