6664728240 has 240 divisors, whose sum is σ = 23284953120. Its totient is φ = 1706987520.

The previous prime is 6664728233. The next prime is 6664728241. The reversal of 6664728240 is 428274666.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is not an unprimeable number, because it can be changed into a prime (6664728241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1886796 + ... + 1890324.

It is an arithmetic number, because the mean of its divisors is an integer number (97020638).

Almost surely, 2^6664728240 is an apocalyptic number.

6664728240 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 6664728240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11642476560).

6664728240 is an abundant number, since it is smaller than the sum of its proper divisors (16620224880).

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

6664728240 is a wasteful number, since it uses less digits than its factorization.

6664728240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3652 (or 3643 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The square root of 6664728240 is about 81637.7868391837. The cubic root of 6664728240 is about 1881.8896271462.

The spelling of 6664728240 in words is "six billion, six hundred sixty-four million, seven hundred twenty-eight thousand, two hundred forty".