561554664 has 64 divisors (see below), whose sum is σ = 1534394880. Its totient is φ = 169848000.

The previous prime is 561554657. The next prime is 561554681. The reversal of 561554664 is 466455165.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164899 + ... + 168269.

It is an arithmetic number, because the mean of its divisors is an integer number (23974920).

Almost surely, 2^561554664 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 561554664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (767197440).

561554664 is an abundant number, since it is smaller than the sum of its proper divisors (972840216).

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

561554664 is a wasteful number, since it uses less digits than its factorization.

561554664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4022 (or 4018 counting only the distinct ones).

The product of its digits is 432000, while the sum is 42.

The square root of 561554664 is about 23697.1446381204. The cubic root of 561554664 is about 825.0191187489.

The spelling of 561554664 in words is "five hundred sixty-one million, five hundred fifty-four thousand, six hundred sixty-four".