66540992000 has 320 divisors, whose sum is σ = 200805111936. Its totient is φ = 21469593600.

The previous prime is 66540991999. The next prime is 66540992009. The reversal of 66540992000 is 29904566.

It is a tau number, because it is divible by the number of its divisors (320).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66540992009) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 7611632 + ... + 7620368.

Almost surely, 2^66540992000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66540992000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100402555968).

66540992000 is an abundant number, since it is smaller than the sum of its proper divisors (134264119936).

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

66540992000 is an equidigital number, since it uses as much as digits as its factorization.

66540992000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8794 (or 8768 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 41.

The spelling of 66540992000 in words is "sixty-six billion, five hundred forty million, nine hundred ninety-two thousand".