66080321 has 2 divisors, whose sum is σ = 66080322. Its totient is φ = 66080320.

The previous prime is 66080303. The next prime is 66080323. The reversal of 66080321 is 12308066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47761921 + 18318400 = 6911^2 + 4280^2 .

It is a cyclic number.

It is not a de Polignac number, because 66080321 - 2²² = 61886017 is a prime.

It is a Sophie Germain prime.

Together with 66080323, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is equal to p_3900626 and since 66080321 and 3900626 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (66080323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33040160 + 33040161.

It is an arithmetic number, because the mean of its divisors is an integer number (33040161).

Almost surely, 2^66080321 is an apocalyptic number.

It is an amenable number.

66080321 is a deficient number, since it is larger than the sum of its proper divisors (1).

66080321 is an equidigital number, since it uses as much as digits as its factorization.

66080321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 66080321 is about 8128.9803173584. The cubic root of 66080321 is about 404.2878731998.

Adding to 66080321 its reverse (12308066), we get a palindrome (78388387).

The spelling of 66080321 in words is "sixty-six million, eighty thousand, three hundred twenty-one".