561440880 has 960 divisors, whose sum is σ = 2729825280. Its totient is φ = 99532800.

The previous prime is 561440821. The next prime is 561440881. The reversal of 561440880 is 88044165.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561440881) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 13693660 + ... + 13693700.

It is an arithmetic number, because the mean of its divisors is an integer number (2843568).

Almost surely, 2^561440880 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 561440880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1364912640).

561440880 is an abundant number, since it is smaller than the sum of its proper divisors (2168384400).

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

561440880 is a wasteful number, since it uses less digits than its factorization.

561440880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 561440880 is about 23694.7437209184. The cubic root of 561440880 is about 824.9633923150.

The spelling of 561440880 in words is "five hundred sixty-one million, four hundred forty thousand, eight hundred eighty".