66106321 has 2 divisors, whose sum is σ = 66106322. Its totient is φ = 66106320.

The previous prime is 66106307. The next prime is 66106333. The reversal of 66106321 is 12360166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57760000 + 8346321 = 7600^2 + 2889^2 .

It is a cyclic number.

It is not a de Polignac number, because 66106321 - 2⁵ = 66106289 is a prime.

It is not a weakly prime, because it can be changed into another prime (66106361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33053160 + 33053161.

It is an arithmetic number, because the mean of its divisors is an integer number (33053161).

Almost surely, 2^66106321 is an apocalyptic number.

It is an amenable number.

66106321 is a deficient number, since it is larger than the sum of its proper divisors (1).

66106321 is an equidigital number, since it uses as much as digits as its factorization.

66106321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 66106321 is about 8130.5793766496. The cubic root of 66106321 is about 404.3408900245.

Adding to 66106321 its reverse (12360166), we get a palindrome (78466487).

The spelling of 66106321 in words is "sixty-six million, one hundred six thousand, three hundred twenty-one".