66228730920 has 512 divisors, whose sum is σ = 264549888000. Its totient is φ = 14547962880.

The previous prime is 66228730879. The next prime is 66228730969. The reversal of 66228730920 is 2903782266.

66228730920 is a `hidden beast` number, since 6 + 62 + 287 + 309 + 2 + 0 = 666.

66228730920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×66228730920³ (a number of 33 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5185182 + ... + 5197938.

It is an arithmetic number, because the mean of its divisors is an integer number (516699000).

Almost surely, 2^66228730920 is an apocalyptic number.

66228730920 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 66228730920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132274944000).

66228730920 is an abundant number, since it is smaller than the sum of its proper divisors (198321157080).

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

66228730920 is a wasteful number, since it uses less digits than its factorization.

66228730920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12830 (or 12820 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 66228730920 in words is "sixty-six billion, two hundred twenty-eight million, seven hundred thirty thousand, nine hundred twenty".