183661 has 2 divisors, whose sum is σ = 183662. Its totient is φ = 183660.

The previous prime is 183637. The next prime is 183683. The reversal of 183661 is 166381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175561 + 8100 = 419^2 + 90^2 .

It is a cyclic number.

It is not a de Polignac number, because 183661 - 2¹⁵ = 150893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (183611) 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, 91830 + 91831.

It is an arithmetic number, because the mean of its divisors is an integer number (91831).

2¹⁸³⁶⁶¹ is an apocalyptic number.

It is an amenable number.

183661 is a deficient number, since it is larger than the sum of its proper divisors (1).

183661 is an equidigital number, since it uses as much as digits as its factorization.

183661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 25.

The square root of 183661 is about 428.5568807055. The cubic root of 183661 is about 56.8423880181.

The spelling of 183661 in words is "one hundred eighty-three thousand, six hundred sixty-one".