561816917568 has 168 divisors, whose sum is σ = 1710722613600. Its totient is φ = 182704481280.

The previous prime is 561816917561. The next prime is 561816917617. The reversal of 561816917568 is 865719618165.

561816917568 is a `hidden beast` number, since 5 + 6 + 1 + 8 + 1 + 69 + 1 + 7 + 568 = 666.

It is not an unprimeable number, because it can be changed into a prime (561816917561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 197083 + ... + 1078181.

It is an arithmetic number, because the mean of its divisors is an integer number (10182872700).

Almost surely, 2^561816917568 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 561816917568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (855361306800).

561816917568 is an abundant number, since it is smaller than the sum of its proper divisors (1148905696032).

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

561816917568 is an equidigital number, since it uses as much as digits as its factorization.

561816917568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881167 (or 881145 counting only the distinct ones).

The product of its digits is 21772800, while the sum is 63.

The spelling of 561816917568 in words is "five hundred sixty-one billion, eight hundred sixteen million, nine hundred seventeen thousand, five hundred sixty-eight".