664578506560 has 112 divisors (see below), whose sum is σ = 1599973814016. Its totient is φ = 262909089792.

The previous prime is 664578506549. The next prime is 664578506567. The reversal of 664578506560 is 65605875466.

It is a junction number, because it is equal to n+sod(n) for n = 664578506495 and 664578506504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664578506567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20973289 + ... + 21004951.

Almost surely, 2^664578506560 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 664578506560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (799986907008).

664578506560 is an abundant number, since it is smaller than the sum of its proper divisors (935395307456).

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

664578506560 is a wasteful number, since it uses less digits than its factorization.

664578506560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32400 (or 32390 counting only the distinct ones).

The product of its (nonzero) digits is 36288000, while the sum is 58.

The spelling of 664578506560 in words is "six hundred sixty-four billion, five hundred seventy-eight million, five hundred six thousand, five hundred sixty".