66189600 has 216 divisors, whose sum is σ = 242211060. Its totient is φ = 16988160.

The previous prime is 66189593. The next prime is 66189601. The reversal of 66189600 is 698166.

It can be written as a sum of positive squares in 6 ways, for example, as 9217296 + 56972304 = 3036^2 + 7548^2 .

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

It is not an unprimeable number, because it can be changed into a prime (66189601) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 208642 + ... + 208958.

Almost surely, 2^66189600 is an apocalyptic number.

66189600 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 66189600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121105530).

66189600 is an abundant number, since it is smaller than the sum of its proper divisors (176021460).

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

66189600 is a wasteful number, since it uses less digits than its factorization.

66189600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372 (or 356 counting only the distinct ones).

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

The square root of 66189600 is about 8135.6991094804. The cubic root of 66189600 is about 404.5106114379.

The spelling of 66189600 in words is "sixty-six million, one hundred eighty-nine thousand, six hundred".