561608640 has 280 divisors, whose sum is σ = 2044671552. Its totient is φ = 146257920.

The previous prime is 561608599. The next prime is 561608683. The reversal of 561608640 is 46806165.

561608640 is a `hidden beast` number, since 5 + 6 + 1 + 6 + 0 + 8 + 640 = 666.

561608640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a junction number, because it is equal to n+sod(n) for n = 561608595 and 561608604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1218010 + ... + 1218470.

Almost surely, 2^561608640 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 561608640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1022335776).

561608640 is an abundant number, since it is smaller than the sum of its proper divisors (1483062912).

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

561608640 is a wasteful number, since it uses less digits than its factorization.

561608640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 518 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 561608640 is about 23698.2834821428. The cubic root of 561608640 is about 825.0455512039.

The spelling of 561608640 in words is "five hundred sixty-one million, six hundred eight thousand, six hundred forty".