66785616 has 60 divisors (see below), whose sum is σ = 188023680. Its totient is φ = 22128960.

The previous prime is 66785611. The next prime is 66785623. The reversal of 66785616 is 61658766.

66785616 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66785611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24481 + ... + 27071.

It is an arithmetic number, because the mean of its divisors is an integer number (3133728).

Almost surely, 2^66785616 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 66785616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94011840).

66785616 is an abundant number, since it is smaller than the sum of its proper divisors (121238064).

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

66785616 is a wasteful number, since it uses less digits than its factorization.

66785616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2784 (or 2775 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 66785616 is about 8172.2466923117. The cubic root of 66785616 is about 405.7211477099.

The spelling of 66785616 in words is "sixty-six million, seven hundred eighty-five thousand, six hundred sixteen".