66685899280 has 360 divisors, whose sum is σ = 213076790784. Its totient is φ = 19184256000.

The previous prime is 66685899257. The next prime is 66685899289. The reversal of 66685899280 is 8299858666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66685899289) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 7282705 + ... + 7291855.

Almost surely, 2^66685899280 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 66685899280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106538395392).

66685899280 is an abundant number, since it is smaller than the sum of its proper divisors (146390891504).

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

66685899280 is a wasteful number, since it uses less digits than its factorization.

66685899280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9215 (or 9189 counting only the distinct ones).

The product of its (nonzero) digits is 89579520, while the sum is 67.

The spelling of 66685899280 in words is "sixty-six billion, six hundred eighty-five million, eight hundred ninety-nine thousand, two hundred eighty".