668286720 has 288 divisors, whose sum is σ = 2417970240. Its totient is φ = 174735360.

The previous prime is 668286709. The next prime is 668286721. The reversal of 668286720 is 27682866.

It is a happy number.

668286720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668286721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2108002 + ... + 2108318.

It is an arithmetic number, because the mean of its divisors is an integer number (8395730).

Almost surely, 2^668286720 is an apocalyptic number.

668286720 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 668286720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1208985120).

668286720 is an abundant number, since it is smaller than the sum of its proper divisors (1749683520).

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

668286720 is a wasteful number, since it uses less digits than its factorization.

668286720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 408 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 668286720 is about 25851.2421365009. The cubic root of 668286720 is about 874.2875157869.

The spelling of 668286720 in words is "six hundred sixty-eight million, two hundred eighty-six thousand, seven hundred twenty".