66641320 has 64 divisors (see below), whose sum is σ = 156119040. Its totient is φ = 25574400.

The previous prime is 66641317. The next prime is 66641363. The reversal of 66641320 is 2314666.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 276400 + ... + 276640.

It is an arithmetic number, because the mean of its divisors is an integer number (2439360).

Almost surely, 2^66641320 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 66641320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78059520).

66641320 is an abundant number, since it is smaller than the sum of its proper divisors (89477720).

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

66641320 is a wasteful number, since it uses less digits than its factorization.

66641320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 66641320 is about 8163.4135017161. The cubic root of 66641320 is about 405.4287386754.

Adding to 66641320 its reverse (2314666), we get a palindrome (68955986).

The spelling of 66641320 in words is "sixty-six million, six hundred forty-one thousand, three hundred twenty".