66539923200 has 216 divisors, whose sum is σ = 243995754800. Its totient is φ = 17743933440.

The previous prime is 66539923189. The next prime is 66539923201. The reversal of 66539923200 is 232993566.

66539923200 is a `hidden beast` number, since 6 + 6 + 539 + 92 + 3 + 20 + 0 = 666.

66539923200 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (216).

It is a super-2 number, since 2×66539923200² (a number of 22 digits) contains 22 as substring.

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 (66539923201) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19735 + ... + 365334.

Almost surely, 2^66539923200 is an apocalyptic number.

66539923200 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 66539923200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121997877400).

66539923200 is an abundant number, since it is smaller than the sum of its proper divisors (177455831600).

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

66539923200 is a wasteful number, since it uses less digits than its factorization.

66539923200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385104 (or 385079 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 45.

The spelling of 66539923200 in words is "sixty-six billion, five hundred thirty-nine million, nine hundred twenty-three thousand, two hundred".