666506550120 has 256 divisors, whose sum is σ = 2072814105600. Its totient is φ = 171336591360.

The previous prime is 666506550089. The next prime is 666506550121. The reversal of 666506550120 is 21055605666.

It is not an unprimeable number, because it can be changed into a prime (666506550121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 143548519 + ... + 143553161.

It is an arithmetic number, because the mean of its divisors is an integer number (8096930100).

Almost surely, 2^666506550120 is an apocalyptic number.

666506550120 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 666506550120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1036407052800).

666506550120 is an abundant number, since it is smaller than the sum of its proper divisors (1406307555480).

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

666506550120 is a wasteful number, since it uses less digits than its factorization.

666506550120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5040 (or 5036 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 42.

The spelling of 666506550120 in words is "six hundred sixty-six billion, five hundred six million, five hundred fifty thousand, one hundred twenty".