66381844320 has 576 divisors, whose sum is σ = 261270696960. Its totient is φ = 15178752000.

The previous prime is 66381844297. The next prime is 66381844357. The reversal of 66381844320 is 2344818366.

66381844320 is a `hidden beast` number, since 6 + 6 + 38 + 184 + 432 + 0 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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 (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 110452020 + ... + 110452620.

It is an arithmetic number, because the mean of its divisors is an integer number (453594960).

Almost surely, 2^66381844320 is an apocalyptic number.

66381844320 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 66381844320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130635348480).

66381844320 is an abundant number, since it is smaller than the sum of its proper divisors (194888852640).

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

66381844320 is a wasteful number, since it uses less digits than its factorization.

66381844320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019 (or 1008 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The spelling of 66381844320 in words is "sixty-six billion, three hundred eighty-one million, eight hundred forty-four thousand, three hundred twenty".