668424856 has 32 divisors (see below), whose sum is σ = 1369645200. Its totient is φ = 303293440.

The previous prime is 668424851. The next prime is 668424859. The reversal of 668424856 is 658424866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668424851) 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 7 ways as a sum of consecutive naturals, for example, 45780 + ... + 58588.

Almost surely, 2^668424856 is an apocalyptic number.

It is an amenable number.

668424856 is an abundant number, since it is smaller than the sum of its proper divisors (701220344).

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

668424856 is a wasteful number, since it uses less digits than its factorization.

668424856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13419 (or 13415 counting only the distinct ones).

The product of its digits is 2211840, while the sum is 49.

The square root of 668424856 is about 25853.9137462783. The cubic root of 668424856 is about 874.3477505417.

It can be divided in two parts, 668 and 424856, that added together give a palindrome (425524).

The spelling of 668424856 in words is "six hundred sixty-eight million, four hundred twenty-four thousand, eight hundred fifty-six".