173230721 has 2 divisors, whose sum is σ = 173230722. Its totient is φ = 173230720.

The previous prime is 173230709. The next prime is 173230741. The reversal of 173230721 is 127032371.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149328400 + 23902321 = 12220^2 + 4889^2 .

It is an emirp because it is prime and its reverse (127032371) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 173230721 - 2¹⁰ = 173229697 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (173230741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86615360 + 86615361.

It is an arithmetic number, because the mean of its divisors is an integer number (86615361).

Almost surely, 2^173230721 is an apocalyptic number.

It is an amenable number.

173230721 is a deficient number, since it is larger than the sum of its proper divisors (1).

173230721 is an equidigital number, since it uses as much as digits as its factorization.

173230721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764, while the sum is 26.

The square root of 173230721 is about 13161.7142120622. The cubic root of 173230721 is about 557.4530607252.

The spelling of 173230721 in words is "one hundred seventy-three million, two hundred thirty thousand, seven hundred twenty-one".