6657239312640 has 864 divisors, whose sum is σ = 26681616089856. Its totient is φ = 1501078487040.

The previous prime is 6657239312611. The next prime is 6657239312663. The reversal of 6657239312640 is 462139327566.

6657239312640 is a `hidden beast` number, since 6 + 6 + 57 + 239 + 312 + 6 + 40 = 666.

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 95 ways as a sum of consecutive naturals, for example, 2761193035 + ... + 2761195445.

It is an arithmetic number, because the mean of its divisors is an integer number (30881500104).

Almost surely, 2^{6657239312640} is an apocalyptic number.

6657239312640 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 6657239312640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13340808044928).

6657239312640 is an abundant number, since it is smaller than the sum of its proper divisors (20024376777216).

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

6657239312640 is a wasteful number, since it uses less digits than its factorization.

6657239312640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2895 (or 2878 counting only the distinct ones).

The product of its (nonzero) digits is 9797760, while the sum is 54.

The spelling of 6657239312640 in words is "six trillion, six hundred fifty-seven billion, two hundred thirty-nine million, three hundred twelve thousand, six hundred forty".