561537216240 has 960 divisors, whose sum is σ = 2419026505728. Its totient is φ = 104778178560.

The previous prime is 561537216223. The next prime is 561537216287. The reversal of 561537216240 is 42612735165.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 561537216192 and 561537216201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 97774809 + ... + 97780551.

Almost surely, 2^561537216240 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 561537216240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1209513252864).

561537216240 is an abundant number, since it is smaller than the sum of its proper divisors (1857489289488).

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

561537216240 is a wasteful number, since it uses less digits than its factorization.

561537216240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5838 (or 5821 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 42.

It can be divided in two parts, 561537 and 216240, that added together give a palindrome (777777).

The spelling of 561537216240 in words is "five hundred sixty-one billion, five hundred thirty-seven million, two hundred sixteen thousand, two hundred forty".