66691392768000 has 9216 divisors, whose sum is σ = 361167772492800. Its totient is φ = 12039487488000.

The previous prime is 66691392767971. The next prime is 66691392768019. The reversal of 66691392768000 is 86729319666.

It is a tau number, because it is divible by the number of its divisors (9216).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

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 767 ways as a sum of consecutive naturals, for example, 3923023103992 + ... + 3923023104008.

It is an arithmetic number, because the mean of its divisors is an integer number (39189211425).

Almost surely, 2^{66691392768000} is an apocalyptic number.

66691392768000 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 66691392768000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180583886246400).

66691392768000 is an abundant number, since it is smaller than the sum of its proper divisors (294476379724800).

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

66691392768000 is a wasteful number, since it uses less digits than its factorization.

66691392768000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 35271936, while the sum is 63.

The spelling of 66691392768000 in words is "sixty-six trillion, six hundred ninety-one billion, three hundred ninety-two million, seven hundred sixty-eight thousand".