66364183440 has 640 divisors, whose sum is σ = 253183795200. Its totient is φ = 15902853120.

The previous prime is 66364183427. The next prime is 66364183447. The reversal of 66364183440 is 4438146366.

It is a happy number.

66364183440 is a `hidden beast` number, since 6 + 636 + 4 + 1 + 8 + 3 + 4 + 4 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (66364183447) by changing a digit.

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 127 ways as a sum of consecutive naturals, for example, 157634430 + ... + 157634850.

It is an arithmetic number, because the mean of its divisors is an integer number (395599680).

Almost surely, 2^66364183440 is an apocalyptic number.

66364183440 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 66364183440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126591897600).

66364183440 is an abundant number, since it is smaller than the sum of its proper divisors (186819611760).

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

66364183440 is a wasteful number, since it uses less digits than its factorization.

66364183440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 652 (or 640 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 45.

The spelling of 66364183440 in words is "sixty-six billion, three hundred sixty-four million, one hundred eighty-three thousand, four hundred forty".