668894828 has 48 divisors (see below), whose sum is σ = 1380746304. Its totient is φ = 277570560.

The previous prime is 668894813. The next prime is 668894857. The reversal of 668894828 is 828498866.

It is an unprimeable number.

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, 155150 + ... + 159402.

It is an arithmetic number, because the mean of its divisors is an integer number (28765548).

Almost surely, 2^668894828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668894828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (690373152).

668894828 is an abundant number, since it is smaller than the sum of its proper divisors (711851476).

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

668894828 is a wasteful number, since it uses less digits than its factorization.

668894828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4442 (or 4440 counting only the distinct ones).

The product of its digits is 10616832, while the sum is 59.

The square root of 668894828 is about 25863.0011406256. The cubic root of 668894828 is about 874.5526215848.

Subtracting from 668894828 its sum of digits (59), we obtain a square (668894769 = 25863²).

It can be divided in two parts, 66889 and 4828, that added together give a palindrome (71717).

The spelling of 668894828 in words is "six hundred sixty-eight million, eight hundred ninety-four thousand, eight hundred twenty-eight".