66638325600 has 432 divisors, whose sum is σ = 292968748800. Its totient is φ = 13846809600.

The previous prime is 66638325581. The next prime is 66638325601. The reversal of 66638325600 is 652383666.

66638325600 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66638325601) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 494301 + ... + 614499.

It is an arithmetic number, because the mean of its divisors is an integer number (678168400).

Almost surely, 2^66638325600 is an apocalyptic number.

66638325600 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 66638325600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146484374400).

66638325600 is an abundant number, since it is smaller than the sum of its proper divisors (226330423200).

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

66638325600 is a wasteful number, since it uses less digits than its factorization.

66638325600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120243 (or 120227 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 45.

The spelling of 66638325600 in words is "sixty-six billion, six hundred thirty-eight million, three hundred twenty-five thousand, six hundred".