223681 has 2 divisors, whose sum is σ = 223682. Its totient is φ = 223680.

The previous prime is 223679. The next prime is 223697. The reversal of 223681 is 186322.

223681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173056 + 50625 = 416^2 + 225^2 .

It is a cyclic number.

It is not a de Polignac number, because 223681 - 2¹ = 223679 is a prime.

It is a super-2 number, since 2×223681² = 100066379522, which contains 22 as substring.

Together with 223679, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 6 and base 12.

It is not a weakly prime, because it can be changed into another prime (223621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111840 + 111841.

It is an arithmetic number, because the mean of its divisors is an integer number (111841).

2²²³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

223681 is a deficient number, since it is larger than the sum of its proper divisors (1).

223681 is an equidigital number, since it uses as much as digits as its factorization.

223681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 22.

The square root of 223681 is about 472.9492573205. The cubic root of 223681 is about 60.7029362209.

The spelling of 223681 in words is "two hundred twenty-three thousand, six hundred eighty-one".