561887616 has 128 divisors (see below), whose sum is σ = 1549951200. Its totient is φ = 180224000.

The previous prime is 561887603. The next prime is 561887633. The reversal of 561887616 is 616788165.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1401016 + ... + 1401416.

Almost surely, 2^561887616 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 561887616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (774975600).

561887616 is an abundant number, since it is smaller than the sum of its proper divisors (988063584).

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

561887616 is a wasteful number, since it uses less digits than its factorization.

561887616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 536 counting only the distinct ones).

The product of its digits is 483840, while the sum is 48.

The square root of 561887616 is about 23704.1687472900. The cubic root of 561887616 is about 825.1821408681.

The spelling of 561887616 in words is "five hundred sixty-one million, eight hundred eighty-seven thousand, six hundred sixteen".