223865 has 4 divisors (see below), whose sum is σ = 268644. Its totient is φ = 179088.

The previous prime is 223849. The next prime is 223903. The reversal of 223865 is 568322.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 568322 = 2 ⋅284161.

It can be written as a sum of positive squares in 2 ways, for example, as 116281 + 107584 = 341^2 + 328^2 .

It is a cyclic number.

It is not a de Polignac number, because 223865 - 2⁴ = 223849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 22382 + ... + 22391.

It is an arithmetic number, because the mean of its divisors is an integer number (67161).

2²²³⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

223865 is a deficient number, since it is larger than the sum of its proper divisors (44779).

223865 is an equidigital number, since it uses as much as digits as its factorization.

223865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44778.

The product of its digits is 2880, while the sum is 26.

The square root of 223865 is about 473.1437413725. The cubic root of 223865 is about 60.7195764050.

The spelling of 223865 in words is "two hundred twenty-three thousand, eight hundred sixty-five".