686222216 has 8 divisors (see below), whose sum is σ = 1286666670. Its totient is φ = 343111104.

The previous prime is 686222213. The next prime is 686222233. The reversal of 686222216 is 612222686.

686222216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 647906116 + 38316100 = 25454^2 + 6190^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (686222213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42888881 + ... + 42888896.

Almost surely, 2^686222216 is an apocalyptic number.

It is an amenable number.

686222216 is a deficient number, since it is larger than the sum of its proper divisors (600444454).

686222216 is a wasteful number, since it uses less digits than its factorization.

686222216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85777783 (or 85777779 counting only the distinct ones).

The product of its digits is 27648, while the sum is 35.

The square root of 686222216 is about 26195.8434870878. The cubic root of 686222216 is about 882.0399541069.

The spelling of 686222216 in words is "six hundred eighty-six million, two hundred twenty-two thousand, two hundred sixteen".