551866 has 8 divisors (see below), whose sum is σ = 946080. Its totient is φ = 236508.

The previous prime is 551861. The next prime is 551909. The reversal of 551866 is 668155.

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

It is not an unprimeable number, because it can be changed into a prime (551861) by changing a digit.

551866 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19696 + ... + 19723.

It is an arithmetic number, because the mean of its divisors is an integer number (118260).

2⁵⁵¹⁸⁶⁶ is an apocalyptic number.

551866 is a deficient number, since it is larger than the sum of its proper divisors (394214).

551866 is a wasteful number, since it uses less digits than its factorization.

551866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39428.

The product of its digits is 7200, while the sum is 31.

The square root of 551866 is about 742.8768403982. The cubic root of 551866 is about 82.0246802569.

The spelling of 551866 in words is "five hundred fifty-one thousand, eight hundred sixty-six".