66388140000 has 1440 divisors, whose sum is σ = 304688593440. Its totient is φ = 13934592000.

The previous prime is 66388139977. The next prime is 66388140031. The reversal of 66388140000 is 4188366.

It is a happy number.

66388140000 is a `hidden beast` number, since 6 + 638 + 8 + 14 + 0 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 343979904 + ... + 343980096.

It is an arithmetic number, because the mean of its divisors is an integer number (211589301).

Almost surely, 2^66388140000 is an apocalyptic number.

66388140000 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 66388140000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152344296720).

66388140000 is an abundant number, since it is smaller than the sum of its proper divisors (238300453440).

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

66388140000 is a wasteful number, since it uses less digits than its factorization.

66388140000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259 (or 223 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 66388140000 in words is "sixty-six billion, three hundred eighty-eight million, one hundred forty thousand".