666789888 has 96 divisors (see below), whose sum is σ = 1821718080. Its totient is φ = 216760320.

The previous prime is 666789887. The next prime is 666789899. The reversal of 666789888 is 888987666.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (666789887) 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 7 ways as a sum of consecutive naturals, for example, 250581 + ... + 253227.

It is an arithmetic number, because the mean of its divisors is an integer number (18976230).

Almost surely, 2^666789888 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 666789888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (910859040).

666789888 is an abundant number, since it is smaller than the sum of its proper divisors (1154928192).

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

666789888 is a wasteful number, since it uses less digits than its factorization.

666789888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2713 (or 2693 counting only the distinct ones).

The product of its digits is 55738368, while the sum is 66.

The square root of 666789888 is about 25822.2750353256. The cubic root of 666789888 is about 873.6342832955.

The spelling of 666789888 in words is "six hundred sixty-six million, seven hundred eighty-nine thousand, eight hundred eighty-eight".