668782218 has 32 divisors (see below), whose sum is σ = 1441440000. Its totient is φ = 205638336.

The previous prime is 668782217. The next prime is 668782259. The reversal of 668782218 is 812287866.

It is a super-2 number, since 2×668782218² = 894539310225999048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668782217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212863 + ... + 215981.

It is an arithmetic number, because the mean of its divisors is an integer number (45045000).

Almost surely, 2^668782218 is an apocalyptic number.

668782218 is an abundant number, since it is smaller than the sum of its proper divisors (772657782).

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

668782218 is a wasteful number, since it uses less digits than its factorization.

668782218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5886.

The product of its digits is 516096, while the sum is 48.

The square root of 668782218 is about 25860.8240007932. The cubic root of 668782218 is about 874.5035411744.

It can be divided in two parts, 66878 and 2218, that added together give a palindrome (69096).

The spelling of 668782218 in words is "six hundred sixty-eight million, seven hundred eighty-two thousand, two hundred eighteen".