6668658720 has 168 divisors, whose sum is σ = 23621666796. Its totient is φ = 1778277888.

The previous prime is 6668658719. The next prime is 6668658739. The reversal of 6668658720 is 278568666.

It can be written as a sum of positive squares in 2 ways, for example, as 6335523216 + 333135504 = 79596^2 + 18252^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 88054 + ... + 145226.

Almost surely, 2^6668658720 is an apocalyptic number.

6668658720 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 6668658720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11810833398).

6668658720 is an abundant number, since it is smaller than the sum of its proper divisors (16953008076).

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

6668658720 is an equidigital number, since it uses as much as digits as its factorization.

6668658720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57206 (or 57183 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The square root of 6668658720 is about 81661.8559671527. The cubic root of 6668658720 is about 1882.2594984895.

The spelling of 6668658720 in words is "six billion, six hundred sixty-eight million, six hundred fifty-eight thousand, seven hundred twenty".