66320320 has 112 divisors (see below), whose sum is σ = 175125888. Its totient is φ = 23720960.

The previous prime is 66320311. The next prime is 66320321. The reversal of 66320320 is 2302366.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 66320291 and 66320300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66320321) 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 15 ways as a sum of consecutive naturals, for example, 292047 + ... + 292273.

It is an arithmetic number, because the mean of its divisors is an integer number (1563624).

Almost surely, 2^66320320 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 66320320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87562944).

66320320 is an abundant number, since it is smaller than the sum of its proper divisors (108805568).

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

66320320 is a wasteful number, since it uses less digits than its factorization.

66320320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338 (or 328 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 22.

The square root of 66320320 is about 8143.7288756441. The cubic root of 66320320 is about 404.7767300595.

Adding to 66320320 its reverse (2302366), we get a palindrome (68622686).

The spelling of 66320320 in words is "sixty-six million, three hundred twenty thousand, three hundred twenty".