8221218 has 16 divisors (see below), whose sum is σ = 16573440. Its totient is φ = 2718576.

The previous prime is 8221211. The next prime is 8221219. The reversal of 8221218 is 8121228.

8221218 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (8221211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4633 + ... + 6156.

It is an arithmetic number, because the mean of its divisors is an integer number (1035840).

Almost surely, 2^8221218 is an apocalyptic number.

8221218 is an abundant number, since it is smaller than the sum of its proper divisors (8352222).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8221218 is a wasteful number, since it uses less digits than its factorization.

8221218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10921.

The product of its digits is 512, while the sum is 24.

The square root of 8221218 is about 2867.2666426407. The cubic root of 8221218 is about 201.8267475022.

The spelling of 8221218 in words is "eight million, two hundred twenty-one thousand, two hundred eighteen".