8217218 has 4 divisors (see below), whose sum is σ = 12325830. Its totient is φ = 4108608.

The previous prime is 8217203. The next prime is 8217221. The reversal of 8217218 is 8127128.

8217218 = 822² + 823² + ... + 833².

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 8196769 + 20449 = 2863^2 + 143^2 .

It is an unprimeable 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 as a sum of consecutive naturals, namely, 2054303 + ... + 2054306.

Almost surely, 2^8217218 is an apocalyptic number.

8217218 is a deficient number, since it is larger than the sum of its proper divisors (4108612).

8217218 is a wasteful number, since it uses less digits than its factorization.

8217218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4108611.

The product of its digits is 1792, while the sum is 29.

The square root of 8217218 is about 2866.5690293450. The cubic root of 8217218 is about 201.7940095326.

The spelling of 8217218 in words is "eight million, two hundred seventeen thousand, two hundred eighteen".