561999 has 8 divisors (see below), whose sum is σ = 773632. Its totient is φ = 362520.

The previous prime is 561997. The next prime is 562007. The reversal of 561999 is 999165.

561999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 561999 - 2¹ = 561997 is a prime.

It is a Duffinian number.

561999 is a modest number, since divided by 999 gives 561 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561997) 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, 2929 + ... + 3114.

It is an arithmetic number, because the mean of its divisors is an integer number (96704).

2⁵⁶¹⁹⁹⁹ is an apocalyptic number.

561999 is a deficient number, since it is larger than the sum of its proper divisors (211633).

561999 is a wasteful number, since it uses less digits than its factorization.

561999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6077.

The product of its digits is 21870, while the sum is 39.

The square root of 561999 is about 749.6659255962. The cubic root of 561999 is about 82.5236663049.

The spelling of 561999 in words is "five hundred sixty-one thousand, nine hundred ninety-nine".