561993866 has 8 divisors (see below), whose sum is σ = 963418080. Its totient is φ = 240854508.

The previous prime is 561993857. The next prime is 561993889. The reversal of 561993866 is 668399165.

561993866 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 a super-4 number, since 4×561993866⁴ (a number of 36 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20071196 + ... + 20071223.

It is an arithmetic number, because the mean of its divisors is an integer number (120427260).

Almost surely, 2^561993866 is an apocalyptic number.

561993866 is a deficient number, since it is larger than the sum of its proper divisors (401424214).

561993866 is a wasteful number, since it uses less digits than its factorization.

561993866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40142428.

The product of its digits is 2099520, while the sum is 53.

The square root of 561993866 is about 23706.4098083198. The cubic root of 561993866 is about 825.2341501278.

The spelling of 561993866 in words is "five hundred sixty-one million, nine hundred ninety-three thousand, eight hundred sixty-six".