666918000 has 480 divisors, whose sum is σ = 2736015360. Its totient is φ = 148262400.

The previous prime is 666917989. The next prime is 666918001. The reversal of 666918000 is 819666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666918001) 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 95 ways as a sum of consecutive naturals, for example, 8441961 + ... + 8442039.

It is an arithmetic number, because the mean of its divisors is an integer number (5700032).

Almost surely, 2^666918000 is an apocalyptic number.

666918000 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 666918000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1368007680).

666918000 is an abundant number, since it is smaller than the sum of its proper divisors (2069097360).

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

666918000 is a wasteful number, since it uses less digits than its factorization.

666918000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 666918000 is about 25824.7555651549. The cubic root of 666918000 is about 873.6902308886.

It can be divided in two parts, 66691 and 8000, that added together give a triangular number (74691 = T₃₈₆).

The spelling of 666918000 in words is "six hundred sixty-six million, nine hundred eighteen thousand".