561813408 has 120 divisors (see below), whose sum is σ = 1779482628. Its totient is φ = 172855296.

The previous prime is 561813401. The next prime is 561813437. The reversal of 561813408 is 804318165.

561813408 is a `hidden beast` number, since 5 + 618 + 1 + 34 + 0 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 559417104 + 2396304 = 23652^2 + 1548^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (561813401) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 25360 + ... + 42032.

Almost surely, 2^561813408 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 561813408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (889741314).

561813408 is an abundant number, since it is smaller than the sum of its proper divisors (1217669220).

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

561813408 is a wasteful number, since it uses less digits than its factorization.

561813408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16708 (or 16691 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 561813408 is about 23702.6034013144. The cubic root of 561813408 is about 825.1458122438.

The spelling of 561813408 in words is "five hundred sixty-one million, eight hundred thirteen thousand, four hundred eight".