173981 has 2 divisors, whose sum is σ = 173982. Its totient is φ = 173980.

The previous prime is 173977. The next prime is 173993. The reversal of 173981 is 189371.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 156025 + 17956 = 395^2 + 134^2 .

It is a cyclic number.

It is not a de Polignac number, because 173981 - 2² = 173977 is a prime.

It is a super-2 number, since 2×173981² = 60538776722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 173981.

It is not a weakly prime, because it can be changed into another prime (173081) 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, 86990 + 86991.

It is an arithmetic number, because the mean of its divisors is an integer number (86991).

2¹⁷³⁹⁸¹ is an apocalyptic number.

It is an amenable number.

173981 is a deficient number, since it is larger than the sum of its proper divisors (1).

173981 is an equidigital number, since it uses as much as digits as its factorization.

173981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1512, while the sum is 29.

The square root of 173981 is about 417.1102971637. The cubic root of 173981 is about 55.8256695998.

The spelling of 173981 in words is "one hundred seventy-three thousand, nine hundred eighty-one".