66388198800 has 1440 divisors, whose sum is σ = 287937126400. Its totient is φ = 13039488000.

The previous prime is 66388198777. The next prime is 66388198817. The reversal of 66388198800 is 889188366.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1543911579 + ... + 1543911621.

Almost surely, 2^66388198800 is an apocalyptic number.

66388198800 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 66388198800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143968563200).

66388198800 is an abundant number, since it is smaller than the sum of its proper divisors (221548927600).

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

66388198800 is a wasteful number, since it uses less digits than its factorization.

66388198800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 57.

The spelling of 66388198800 in words is "sixty-six billion, three hundred eighty-eight million, one hundred ninety-eight thousand, eight hundred".