8218642 has 4 divisors (see below), whose sum is σ = 12327966. Its totient is φ = 4109320.

The previous prime is 8218619. The next prime is 8218663. The reversal of 8218642 is 2468128.

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., 6205081 + 2013561 = 2491^2 + 1419^2 .

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, 2054659 + ... + 2054662.

Almost surely, 2^8218642 is an apocalyptic number.

8218642 is a deficient number, since it is larger than the sum of its proper divisors (4109324).

8218642 is a wasteful number, since it uses less digits than its factorization.

8218642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4109323.

The product of its digits is 6144, while the sum is 31.

The square root of 8218642 is about 2866.8173991379. The cubic root of 8218642 is about 201.8056654674.

It can be divided in two parts, 82186 and 42, that added together give a palindrome (82228).

The spelling of 8218642 in words is "eight million, two hundred eighteen thousand, six hundred forty-two".