561129120 has 240 divisors, whose sum is σ = 2049977160. Its totient is φ = 144377856.

The previous prime is 561129097. The next prime is 561129139. The reversal of 561129120 is 21921165.

561129120 is a `hidden beast` number, since 5 + 611 + 29 + 1 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 529184016 + 31945104 = 23004^2 + 5652^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 375094 + ... + 376586.

Almost surely, 2^561129120 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 561129120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1024988580).

561129120 is an abundant number, since it is smaller than the sum of its proper divisors (1488848040).

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

561129120 is a wasteful number, since it uses less digits than its factorization.

561129120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1549 (or 1532 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 561129120 is about 23688.1641331700. The cubic root of 561129120 is about 824.8106672964.

The spelling of 561129120 in words is "five hundred sixty-one million, one hundred twenty-nine thousand, one hundred twenty".