561611166 has 16 divisors (see below), whose sum is σ = 1128173184. Its totient is φ = 186378584.

The previous prime is 561611077. The next prime is 561611189. The reversal of 561611166 is 661116165.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204810 + ... + 207533.

It is an arithmetic number, because the mean of its divisors is an integer number (70510824).

Almost surely, 2^561611166 is an apocalyptic number.

561611166 is an abundant number, since it is smaller than the sum of its proper divisors (566562018).

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

561611166 is a wasteful number, since it uses less digits than its factorization.

561611166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412575.

The product of its digits is 6480, while the sum is 33.

The square root of 561611166 is about 23698.3367770821. The cubic root of 561611166 is about 825.0467881637.

The spelling of 561611166 in words is "five hundred sixty-one million, six hundred eleven thousand, one hundred sixty-six".