561998 has 8 divisors (see below), whose sum is σ = 846192. Its totient is φ = 279936.

The previous prime is 561997. The next prime is 562007. The reversal of 561998 is 899165.

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

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 561998.

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 3 ways as a sum of consecutive naturals, for example, 686 + ... + 1262.

It is an arithmetic number, because the mean of its divisors is an integer number (105774).

2⁵⁶¹⁹⁹⁸ is an apocalyptic number.

561998 is a deficient number, since it is larger than the sum of its proper divisors (284194).

561998 is a wasteful number, since it uses less digits than its factorization.

561998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066.

The product of its digits is 19440, while the sum is 38.

The square root of 561998 is about 749.6652586321. The cubic root of 561998 is about 82.5236173584.

The spelling of 561998 in words is "five hundred sixty-one thousand, nine hundred ninety-eight".