173066221 has 2 divisors, whose sum is σ = 173066222. Its totient is φ = 173066220.

The previous prime is 173066219. The next prime is 173066297. The reversal of 173066221 is 122660371.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 164737225 + 8328996 = 12835^2 + 2886^2 .

It is a cyclic number.

It is not a de Polignac number, because 173066221 - 2¹ = 173066219 is a prime.

Together with 173066219, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 173066221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (173066321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86533110 + 86533111.

It is an arithmetic number, because the mean of its divisors is an integer number (86533111).

Almost surely, 2^173066221 is an apocalyptic number.

It is an amenable number.

173066221 is a deficient number, since it is larger than the sum of its proper divisors (1).

173066221 is an equidigital number, since it uses as much as digits as its factorization.

173066221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 173066221 is about 13155.4635418141. The cubic root of 173066221 is about 557.2765522520.

The spelling of 173066221 in words is "one hundred seventy-three million, sixty-six thousand, two hundred twenty-one".