173561 has 2 divisors, whose sum is σ = 173562. Its totient is φ = 173560.

The previous prime is 173549. The next prime is 173573. The reversal of 173561 is 165371.

It is a balanced prime because it is at equal distance from previous prime (173549) and next prime (173573).

It can be written as a sum of positive squares in only one way, i.e., 118336 + 55225 = 344^2 + 235^2 .

It is a cyclic number.

It is not a de Polignac number, because 173561 - 2⁶ = 173497 is a prime.

It is not a weakly prime, because it can be changed into another prime (173501) 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, 86780 + 86781.

It is an arithmetic number, because the mean of its divisors is an integer number (86781).

2¹⁷³⁵⁶¹ is an apocalyptic number.

It is an amenable number.

173561 is a deficient number, since it is larger than the sum of its proper divisors (1).

173561 is an equidigital number, since it uses as much as digits as its factorization.

173561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 630, while the sum is 23.

The square root of 173561 is about 416.6065289935. The cubic root of 173561 is about 55.7807112924.

The spelling of 173561 in words is "one hundred seventy-three thousand, five hundred sixty-one".