561600661 has 8 divisors (see below), whose sum is σ = 594869184. Its totient is φ = 528358080.

The previous prime is 561600653. The next prime is 561600713. The reversal of 561600661 is 166006165.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 561600661 - 2³ = 561600653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561600601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54616 + ... + 64078.

It is an arithmetic number, because the mean of its divisors is an integer number (74358648).

Almost surely, 2^561600661 is an apocalyptic number.

It is an amenable number.

561600661 is a deficient number, since it is larger than the sum of its proper divisors (33268523).

561600661 is a wasteful number, since it uses less digits than its factorization.

561600661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12971.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 561600661 is about 23698.1151360187. The cubic root of 561600661 is about 825.0416439340.

The spelling of 561600661 in words is "five hundred sixty-one million, six hundred thousand, six hundred sixty-one".