66481990000 has 100 divisors (see below), whose sum is σ = 162137774304. Its totient is φ = 26398144000.

The previous prime is 66481989971. The next prime is 66481990007. The reversal of 66481990000 is 9918466.

It is a tau number, because it is divible by the number of its divisors (100).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66481990007) 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 19 ways as a sum of consecutive naturals, for example, 1345737 + ... + 1394263.

Almost surely, 2^66481990000 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 66481990000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81068887152).

66481990000 is an abundant number, since it is smaller than the sum of its proper divisors (95655784304).

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

66481990000 is a wasteful number, since it uses less digits than its factorization.

66481990000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48692 (or 48671 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 43.

The spelling of 66481990000 in words is "sixty-six billion, four hundred eighty-one million, nine hundred ninety thousand".