66624566400 has 576 divisors, whose sum is σ = 274574926080. Its totient is φ = 15067054080.

The previous prime is 66624566399. The next prime is 66624566441. The reversal of 66624566400 is 466542666.

It is a tau number, because it is divible by the number of its divisors (576).

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

It is a congruent number.

It is an unprimeable number.

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 71 ways as a sum of consecutive naturals, for example, 19553497 + ... + 19556903.

It is an arithmetic number, because the mean of its divisors is an integer number (476692580).

Almost surely, 2^66624566400 is an apocalyptic number.

66624566400 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 66624566400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137287463040).

66624566400 is an abundant number, since it is smaller than the sum of its proper divisors (207950359680).

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

66624566400 is a wasteful number, since it uses less digits than its factorization.

66624566400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3541 (or 3521 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 45.

The spelling of 66624566400 in words is "sixty-six billion, six hundred twenty-four million, five hundred sixty-six thousand, four hundred".