561081996 has 18 divisors (see below), whose sum is σ = 1418290692. Its totient is φ = 187027320.

The previous prime is 561081959. The next prime is 561082003. The reversal of 561081996 is 699180165.

561081996 is a `hidden beast` number, since 561 + 0 + 81 + 9 + 9 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7792770 + ... + 7792841.

Almost surely, 2^561081996 is an apocalyptic number.

It is an amenable number.

561081996 is an abundant number, since it is smaller than the sum of its proper divisors (857208696).

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

561081996 is a wasteful number, since it uses less digits than its factorization.

561081996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15585621 (or 15585616 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 561081996 is about 23687.1694383267. The cubic root of 561081996 is about 824.7875772656.

The spelling of 561081996 in words is "five hundred sixty-one million, eighty-one thousand, nine hundred ninety-six".