66709782144 has 192 divisors, whose sum is σ = 209152468800. Its totient is φ = 20928245760.

The previous prime is 66709782131. The next prime is 66709782151. The reversal of 66709782144 is 44128790766.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 965389 + ... + 1032179.

It is an arithmetic number, because the mean of its divisors is an integer number (1089335775).

Almost surely, 2^66709782144 is an apocalyptic number.

66709782144 is a gapful number since it is divisible by the number (64) 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 66709782144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104576234400).

66709782144 is an abundant number, since it is smaller than the sum of its proper divisors (142442686656).

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

66709782144 is a wasteful number, since it uses less digits than its factorization.

66709782144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66848 (or 66813 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 54.

The spelling of 66709782144 in words is "sixty-six billion, seven hundred nine million, seven hundred eighty-two thousand, one hundred forty-four".