181361 has 2 divisors, whose sum is σ = 181362. Its totient is φ = 181360.

The previous prime is 181303. The next prime is 181387. The reversal of 181361 is 163181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 102400 + 78961 = 320^2 + 281^2 .

It is an emirp because it is prime and its reverse (163181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181361 - 2⁶ = 181297 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 181361.

It is not a weakly prime, because it can be changed into another prime (181301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90680 + 90681.

It is an arithmetic number, because the mean of its divisors is an integer number (90681).

2¹⁸¹³⁶¹ is an apocalyptic number.

It is an amenable number.

181361 is a deficient number, since it is larger than the sum of its proper divisors (1).

181361 is an equidigital number, since it uses as much as digits as its factorization.

181361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144, while the sum is 20.

The square root of 181361 is about 425.8650020840. The cubic root of 181361 is about 56.6041101287.

It can be divided in two parts, 181 and 361, that multiplied together give a triangular number (65341 = T₃₆₁).

The spelling of 181361 in words is "one hundred eighty-one thousand, three hundred sixty-one".