66281724447 has 16 divisors (see below), whose sum is σ = 93034235520. Its totient is φ = 41858877600.

The previous prime is 66281724403. The next prime is 66281724451. The reversal of 66281724447 is 74442718266.

It is a happy number.

It is not a de Polignac number, because 66281724447 - 2⁸ = 66281724191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66281724447.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66281724647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 843672 + ... + 918882.

It is an arithmetic number, because the mean of its divisors is an integer number (5814639720).

Almost surely, 2^66281724447 is an apocalyptic number.

66281724447 is a deficient number, since it is larger than the sum of its proper divisors (26752511073).

66281724447 is a wasteful number, since it uses less digits than its factorization.

66281724447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90694.

The product of its digits is 3612672, while the sum is 51.

The spelling of 66281724447 in words is "sixty-six billion, two hundred eighty-one million, seven hundred twenty-four thousand, four hundred forty-seven".