866222 has 12 divisors (see below), whose sum is σ = 1511640. Its totient is φ = 371196.

The previous prime is 866221. The next prime is 866231. The reversal of 866222 is 222668.

866222 = T₁₆₃ + T₁₆₄ + ... + T₂₁₁.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 866191 and 866200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4322 + ... + 4517.

It is an arithmetic number, because the mean of its divisors is an integer number (125970).

2⁸⁶⁶²²² is an apocalyptic number.

866222 is a deficient number, since it is larger than the sum of its proper divisors (645418).

866222 is a wasteful number, since it uses less digits than its factorization.

866222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8855 (or 8848 counting only the distinct ones).

The product of its digits is 2304, while the sum is 26.

The square root of 866222 is about 930.7104812991. The cubic root of 866222 is about 95.3256414918.

The spelling of 866222 in words is "eight hundred sixty-six thousand, two hundred twenty-two".