66289824 has 72 divisors (see below), whose sum is σ = 195036660. Its totient is φ = 21331968.

The previous prime is 66289823. The next prime is 66289831. The reversal of 66289824 is 42898266.

It can be written as a sum of positive squares in 2 ways, for example, as 58064400 + 8225424 = 7620^2 + 2868^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 66289824.

It is not an unprimeable number, because it can be changed into a prime (66289823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4384 + ... + 12320.

Almost surely, 2^66289824 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66289824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97518330).

66289824 is an abundant number, since it is smaller than the sum of its proper divisors (128746836).

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

66289824 is a wasteful number, since it uses less digits than its factorization.

66289824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7982 (or 7971 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The square root of 66289824 is about 8141.8562993951. The cubic root of 66289824 is about 404.7146778675.

The spelling of 66289824 in words is "sixty-six million, two hundred eighty-nine thousand, eight hundred twenty-four".