561787904 has 44 divisors (see below), whose sum is σ = 1150504068. Its totient is φ = 274022400.

The previous prime is 561787879. The next prime is 561787937. The reversal of 561787904 is 409787165.

It can be written as a sum of positive squares in 2 ways, for example, as 45589504 + 516198400 = 6752^2 + 22720^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35294 + ... + 48674.

Almost surely, 2^561787904 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 561787904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (575252034).

561787904 is an abundant number, since it is smaller than the sum of its proper divisors (588716164).

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

561787904 is a wasteful number, since it uses less digits than its factorization.

561787904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13442 (or 13424 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 47.

The square root of 561787904 is about 23702.0653952351. The cubic root of 561787904 is about 825.1333259884.

The spelling of 561787904 in words is "five hundred sixty-one million, seven hundred eighty-seven thousand, nine hundred four".