561966 has 16 divisors (see below), whose sum is σ = 1131600. Its totient is φ = 186048.

The previous prime is 561961. The next prime is 561973. The reversal of 561966 is 669165.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561961) by changing a digit.

561966 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1170 + ... + 1578.

It is an arithmetic number, because the mean of its divisors is an integer number (70725).

2⁵⁶¹⁹⁶⁶ is an apocalyptic number.

561966 is an abundant number, since it is smaller than the sum of its proper divisors (569634).

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

561966 is a wasteful number, since it uses less digits than its factorization.

561966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643.

The product of its digits is 9720, while the sum is 33.

The square root of 561966 is about 749.6439154692. The cubic root of 561966 is about 82.5220510385.

The spelling of 561966 in words is "five hundred sixty-one thousand, nine hundred sixty-six".