166822321 has 2 divisors, whose sum is σ = 166822322. Its totient is φ = 166822320.

The previous prime is 166822319. The next prime is 166822333. The reversal of 166822321 is 123228661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 142468096 + 24354225 = 11936^2 + 4935^2 .

It is a cyclic number.

It is not a de Polignac number, because 166822321 - 2¹ = 166822319 is a prime.

Together with 166822319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (166822021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83411160 + 83411161.

It is an arithmetic number, because the mean of its divisors is an integer number (83411161).

Almost surely, 2^166822321 is an apocalyptic number.

It is an amenable number.

166822321 is a deficient number, since it is larger than the sum of its proper divisors (1).

166822321 is an equidigital number, since it uses as much as digits as its factorization.

166822321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 31.

The square root of 166822321 is about 12915.9715468872. The cubic root of 166822321 is about 550.4924746050.

The spelling of 166822321 in words is "one hundred sixty-six million, eight hundred twenty-two thousand, three hundred twenty-one".