66120075856800 has 2592 divisors, whose sum is σ = 291890116836864. Its totient is φ = 14562867916800.

The previous prime is 66120075856799. The next prime is 66120075856829. The reversal of 66120075856800 is 865857002166.

66120075856800 is a `hidden beast` number, since 6 + 6 + 1 + 2 + 0 + 0 + 75 + 8 + 568 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2592).

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 431 ways as a sum of consecutive naturals, for example, 283777149484 + ... + 283777149716.

It is an arithmetic number, because the mean of its divisors is an integer number (112611927792).

Almost surely, 2^{66120075856800} is an apocalyptic number.

66120075856800 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 66120075856800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145945058418432).

66120075856800 is an abundant number, since it is smaller than the sum of its proper divisors (225770040980064).

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

66120075856800 is an equidigital number, since it uses as much as digits as its factorization.

66120075856800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375 (or 281 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 54.

The spelling of 66120075856800 in words is "sixty-six trillion, one hundred twenty billion, seventy-five million, eight hundred fifty-six thousand, eight hundred".