668450880 has 560 divisors, whose sum is σ = 2648779056. Its totient is φ = 159252480.

The previous prime is 668450879. The next prime is 668450903. The reversal of 668450880 is 88054866.

668450880 is a `hidden beast` number, since 6 + 68 + 4 + 508 + 80 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 331776 + 668119104 = 576^2 + 25848^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 16303660 + ... + 16303700.

Almost surely, 2^668450880 is an apocalyptic number.

668450880 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668450880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1324389528).

668450880 is an abundant number, since it is smaller than the sum of its proper divisors (1980328176).

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

668450880 is a wasteful number, since it uses less digits than its factorization.

668450880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 668450880 is about 25854.4170307512. The cubic root of 668450880 is about 874.3590974819.

The spelling of 668450880 in words is "six hundred sixty-eight million, four hundred fifty thousand, eight hundred eighty".