66506872320 has 960 divisors, whose sum is σ = 282386497536. Its totient is φ = 14120386560.

The previous prime is 66506872309. The next prime is 66506872321. The reversal of 66506872320 is 2327860566.

It is a happy number.

66506872320 is a `hidden beast` number, since 66 + 506 + 87 + 2 + 3 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

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 (66506872321) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 348203425 + ... + 348203615.

Almost surely, 2^66506872320 is an apocalyptic number.

66506872320 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 66506872320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141193248768).

66506872320 is an abundant number, since it is smaller than the sum of its proper divisors (215879625216).

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

66506872320 is a wasteful number, since it uses less digits than its factorization.

66506872320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 352 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 66506872320 in words is "sixty-six billion, five hundred six million, eight hundred seventy-two thousand, three hundred twenty".